From: Matthias Maier <tamiko@43-1.org>
Date: Wed, 21 Feb 2024 08:02:51 +0000 (-0600)
Subject: Update license headers: ./doc
X-Git-Tag: v9.6.0-rc1~525^2~3
X-Git-Url: https://gitweb.dealii.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3636b27dec0cfa80483c062ab0137964c40d50a3;p=dealii.git

Update license headers: ./doc
---

diff --git a/doc/CMakeLists.txt b/doc/CMakeLists.txt
index 9061a65de2..7617983f1a 100644
--- a/doc/CMakeLists.txt
+++ b/doc/CMakeLists.txt
@@ -1,17 +1,15 @@
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 ##
 ## Copyright (C) 2012 - 2022 by the deal.II Authors
 ##
 ## This file is part of the deal.II library.
 ##
-## The deal.II library is free software; you can use it, redistribute
-## it, and/or modify it under the terms of the GNU Lesser General
-## Public License as published by the Free Software Foundation; either
-## version 2.1 of the License, or (at your option) any later version.
-## The full text of the license can be found in the file LICENSE.md at
-## the top level directory of deal.II.
+## Part of the source code is dual licensed under Apache-2.0 WITH
+## LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+## governing the source code and code contributions can be found in
+## LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 ##
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 
 #
 # Set up all necessary bits for the documentation
diff --git a/doc/developers/testsuite.html b/doc/developers/testsuite.html
index acb8283287..c7d5041b37 100644
--- a/doc/developers/testsuite.html
+++ b/doc/developers/testsuite.html
@@ -650,20 +650,19 @@ category/test.run_only
       and modify it to where it does what we'd like to test. Alternatively,
       you can also start from a template like this:
 <pre>
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2015 - 2024 by the deal.II Authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2024 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 // a short (a few lines) description of what the program does
 
diff --git a/doc/doxygen/CMakeLists.txt b/doc/doxygen/CMakeLists.txt
index 69f1d4cdc4..62b89da009 100644
--- a/doc/doxygen/CMakeLists.txt
+++ b/doc/doxygen/CMakeLists.txt
@@ -1,17 +1,16 @@
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 ##
+## SPDX-License-Identifier: LGPL-2.1-or-later
 ## Copyright (C) 2012 - 2023 by the deal.II authors
 ##
 ## This file is part of the deal.II library.
 ##
-## The deal.II library is free software; you can use it, redistribute
-## it, and/or modify it under the terms of the GNU Lesser General
-## Public License as published by the Free Software Foundation; either
-## version 2.1 of the License, or (at your option) any later version.
-## The full text of the license can be found in the file LICENSE.md at
-## the top level directory of deal.II.
+## Part of the source code is dual licensed under Apache-2.0 WITH
+## LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+## governing the source code and code contributions can be found in
+## LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 ##
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 
 #
 # Generate the source documentation via doxygen:
diff --git a/doc/doxygen/code-gallery/CMakeLists.txt b/doc/doxygen/code-gallery/CMakeLists.txt
index 771febf819..b3d71a5f13 100644
--- a/doc/doxygen/code-gallery/CMakeLists.txt
+++ b/doc/doxygen/code-gallery/CMakeLists.txt
@@ -1,17 +1,15 @@
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 ##
 ## Copyright (C) 2015 - 2023 by the deal.II Authors
 ##
 ## This file is part of the deal.II library.
 ##
-## The deal.II library is free software; you can use it, redistribute
-## it, and/or modify it under the terms of the GNU Lesser General
-## Public License as published by the Free Software Foundation; either
-## version 2.1 of the License, or (at your option) any later version.
-## The full text of the license can be found in the file LICENSE.md at
-## the top level directory of deal.II.
+## Part of the source code is dual licensed under Apache-2.0 WITH
+## LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+## governing the source code and code contributions can be found in
+## LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 ##
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 
 
 
diff --git a/doc/doxygen/code-gallery/code-gallery.h.in b/doc/doxygen/code-gallery/code-gallery.h.in
index 2d00f89ed1..c57196b343 100644
--- a/doc/doxygen/code-gallery/code-gallery.h.in
+++ b/doc/doxygen/code-gallery/code-gallery.h.in
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2016 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/code-gallery/no-code-gallery.h b/doc/doxygen/code-gallery/no-code-gallery.h
index f929b8a495..a9fc45c684 100644
--- a/doc/doxygen/code-gallery/no-code-gallery.h
+++ b/doc/doxygen/code-gallery/no-code-gallery.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2016 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/extra.sty b/doc/doxygen/extra.sty
index 3e688da0ed..a5e13c2fe3 100644
--- a/doc/doxygen/extra.sty
+++ b/doc/doxygen/extra.sty
@@ -1,17 +1,16 @@
-% ---------------------------------------------------------------------
+%  ------------------------------------------------------------------------
 %
-% Copyright (C) 2019 by the deal.II authors
+%  SPDX-License-Identifier: LGPL-2.1-or-later
+%  Copyright (C) 2019 - 2020 by the deal.II authors
 %
-% This file is part of the deal.II library.
+%  This file is part of the deal.II library.
 %
-% The deal.II library is free software; you can use it, redistribute
-% it, and/or modify it under the terms of the GNU Lesser General
-% Public License as published by the Free Software Foundation; either
-% version 2.1 of the License, or (at your option) any later version.
-% The full text of the license can be found in the file LICENSE.md at
-% the top level directory of deal.II.
+%  Part of the source code is dual licensed under Apache-2.0 WITH
+%  LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+%  governing the source code and code contributions can be found in
+%  LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 %
-% ---------------------------------------------------------------------
+%  ------------------------------------------------------------------------
 
 % export dealcoloneq (this file is used when generating the formulas as images
 % in the doxygen HTML output (without mathjax).
diff --git a/doc/doxygen/headers/automatic_and_symbolic_differentiation.h b/doc/doxygen/headers/automatic_and_symbolic_differentiation.h
index 73cbd8fcc5..595ce3ce47 100644
--- a/doc/doxygen/headers/automatic_and_symbolic_differentiation.h
+++ b/doc/doxygen/headers/automatic_and_symbolic_differentiation.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2017 - 2022 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @defgroup auto_symb_diff Automatic and symbolic differentiation
diff --git a/doc/doxygen/headers/c++.h b/doc/doxygen/headers/c++.h
index a6f607df7e..c34798af63 100644
--- a/doc/doxygen/headers/c++.h
+++ b/doc/doxygen/headers/c++.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2014 - 2023 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2020 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/coding_conventions.h b/doc/doxygen/headers/coding_conventions.h
index 4b98964167..92df3f8a94 100644
--- a/doc/doxygen/headers/coding_conventions.h
+++ b/doc/doxygen/headers/coding_conventions.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 1998 - 2023 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2007 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/concepts.h b/doc/doxygen/headers/concepts.h
index cf7916ba67..c065a6d991 100644
--- a/doc/doxygen/headers/concepts.h
+++ b/doc/doxygen/headers/concepts.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2015 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/constraints.h b/doc/doxygen/headers/constraints.h
index b2deeacd87..e20b83cfd5 100644
--- a/doc/doxygen/headers/constraints.h
+++ b/doc/doxygen/headers/constraints.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2010 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/cuda.h b/doc/doxygen/headers/cuda.h
index e63b1f57a5..59aab0e0a2 100644
--- a/doc/doxygen/headers/cuda.h
+++ b/doc/doxygen/headers/cuda.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2018 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/distributed.h b/doc/doxygen/headers/distributed.h
index d6fc058536..0b461f744e 100644
--- a/doc/doxygen/headers/distributed.h
+++ b/doc/doxygen/headers/distributed.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2009 - 2023 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2010 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/dofs.h b/doc/doxygen/headers/dofs.h
index 493d5b7de5..2cc5afa5e0 100644
--- a/doc/doxygen/headers/dofs.h
+++ b/doc/doxygen/headers/dofs.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2003 - 2023 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2006 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/exceptions.h b/doc/doxygen/headers/exceptions.h
index 925ac7fc1d..08a251c61b 100644
--- a/doc/doxygen/headers/exceptions.h
+++ b/doc/doxygen/headers/exceptions.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2003 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/fe.h b/doc/doxygen/headers/fe.h
index f5c3fd7cee..b7c4eab367 100644
--- a/doc/doxygen/headers/fe.h
+++ b/doc/doxygen/headers/fe.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2003 - 2020 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2006 - 2020 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/fe_vs_mapping_vs_fevalues.h b/doc/doxygen/headers/fe_vs_mapping_vs_fevalues.h
index 3587e7ce53..b05aacf917 100644
--- a/doc/doxygen/headers/fe_vs_mapping_vs_fevalues.h
+++ b/doc/doxygen/headers/fe_vs_mapping_vs_fevalues.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2015 - 2020 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/functions.h b/doc/doxygen/headers/functions.h
index b499ae118f..d4d6533284 100644
--- a/doc/doxygen/headers/functions.h
+++ b/doc/doxygen/headers/functions.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2006 - 2020 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/geodynamics.h b/doc/doxygen/headers/geodynamics.h
index f5859f8060..58b575fb8f 100644
--- a/doc/doxygen/headers/geodynamics.h
+++ b/doc/doxygen/headers/geodynamics.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2009 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/geometry_and_primitives.h b/doc/doxygen/headers/geometry_and_primitives.h
index 72ebd57105..f163020a33 100644
--- a/doc/doxygen/headers/geometry_and_primitives.h
+++ b/doc/doxygen/headers/geometry_and_primitives.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2006 - 2021 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/global_dof_index.h b/doc/doxygen/headers/global_dof_index.h
index 892a1007b1..a06286b436 100644
--- a/doc/doxygen/headers/global_dof_index.h
+++ b/doc/doxygen/headers/global_dof_index.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2013 - 2018 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/glossary.h b/doc/doxygen/headers/glossary.h
index 5140e1769e..c5f887924a 100644
--- a/doc/doxygen/headers/glossary.h
+++ b/doc/doxygen/headers/glossary.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2005 - 2024 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/grid.h b/doc/doxygen/headers/grid.h
index 2a72928341..7a0f3bd4fb 100644
--- a/doc/doxygen/headers/grid.h
+++ b/doc/doxygen/headers/grid.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2003 - 2022 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2006 - 2022 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/hp.h b/doc/doxygen/headers/hp.h
index 1ea8bcfa2c..45062c1d09 100644
--- a/doc/doxygen/headers/hp.h
+++ b/doc/doxygen/headers/hp.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2003 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/instantiations.h b/doc/doxygen/headers/instantiations.h
index 796fe6f163..ebf752bf82 100644
--- a/doc/doxygen/headers/instantiations.h
+++ b/doc/doxygen/headers/instantiations.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2005 - 2020 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/integrators.h b/doc/doxygen/headers/integrators.h
index 380bdb0694..c4ab9d1406 100644
--- a/doc/doxygen/headers/integrators.h
+++ b/doc/doxygen/headers/integrators.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2010 - 2014 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/io.h b/doc/doxygen/headers/io.h
index 4cbcf5e29e..f60fe51b8e 100644
--- a/doc/doxygen/headers/io.h
+++ b/doc/doxygen/headers/io.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2005 - 2020 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2006 - 2020 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/iterators.h b/doc/doxygen/headers/iterators.h
index 6aa2d4f1e4..9a518c268a 100644
--- a/doc/doxygen/headers/iterators.h
+++ b/doc/doxygen/headers/iterators.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2013 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  @defgroup Iterators Iterators on mesh-like containers
diff --git a/doc/doxygen/headers/lac.h b/doc/doxygen/headers/lac.h
index ac77c1fb63..9ceb088a30 100644
--- a/doc/doxygen/headers/lac.h
+++ b/doc/doxygen/headers/lac.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2003 - 2015 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 
diff --git a/doc/doxygen/headers/laoperators.h b/doc/doxygen/headers/laoperators.h
index 6d0d705b00..096773187b 100644
--- a/doc/doxygen/headers/laoperators.h
+++ b/doc/doxygen/headers/laoperators.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2015 - 2021 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 
diff --git a/doc/doxygen/headers/main.h b/doc/doxygen/headers/main.h
index df9986189e..ded5f74cb0 100644
--- a/doc/doxygen/headers/main.h
+++ b/doc/doxygen/headers/main.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2006 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/manifold.h b/doc/doxygen/headers/manifold.h
index fb7107a8c2..5a3e37e477 100644
--- a/doc/doxygen/headers/manifold.h
+++ b/doc/doxygen/headers/manifold.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2003 - 2022 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2014 - 2022 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/matrices.h b/doc/doxygen/headers/matrices.h
index 454e91ab43..f2ab43f8f0 100644
--- a/doc/doxygen/headers/matrices.h
+++ b/doc/doxygen/headers/matrices.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2003 - 2015 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2006 - 2015 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 
diff --git a/doc/doxygen/headers/matrixfree.h b/doc/doxygen/headers/matrixfree.h
index 2751cb5818..225713eb61 100644
--- a/doc/doxygen/headers/matrixfree.h
+++ b/doc/doxygen/headers/matrixfree.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2018 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/memory.h b/doc/doxygen/headers/memory.h
index 0b867a8ce9..a15d117a5c 100644
--- a/doc/doxygen/headers/memory.h
+++ b/doc/doxygen/headers/memory.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2006 - 2015 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/mesh_worker.h b/doc/doxygen/headers/mesh_worker.h
index 5bb69c7862..270fb86fe2 100644
--- a/doc/doxygen/headers/mesh_worker.h
+++ b/doc/doxygen/headers/mesh_worker.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2010 - 2014 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 
diff --git a/doc/doxygen/headers/mg.h b/doc/doxygen/headers/mg.h
index 8dc768a868..37d37442ef 100644
--- a/doc/doxygen/headers/mg.h
+++ b/doc/doxygen/headers/mg.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2003 - 2020 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/multithreading.h b/doc/doxygen/headers/multithreading.h
index 0d13c85289..c15bad9ff7 100644
--- a/doc/doxygen/headers/multithreading.h
+++ b/doc/doxygen/headers/multithreading.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2006 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/namespace_dealii.h b/doc/doxygen/headers/namespace_dealii.h
index 5c808c1006..80659e73e7 100644
--- a/doc/doxygen/headers/namespace_dealii.h
+++ b/doc/doxygen/headers/namespace_dealii.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2013 - 2014 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * This is the namespace in which everything in deal.II is. To avoid prefixing
diff --git a/doc/doxygen/headers/numerical_algorithms.h b/doc/doxygen/headers/numerical_algorithms.h
index 3dbd2fbb6a..a126325ac4 100644
--- a/doc/doxygen/headers/numerical_algorithms.h
+++ b/doc/doxygen/headers/numerical_algorithms.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2006 - 2015 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/parallel.h b/doc/doxygen/headers/parallel.h
index f5fb3f11f4..e9aee2de9e 100644
--- a/doc/doxygen/headers/parallel.h
+++ b/doc/doxygen/headers/parallel.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2009 - 2022 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2010 - 2022 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/petsc.h b/doc/doxygen/headers/petsc.h
index 81c4acb393..1aed3932c0 100644
--- a/doc/doxygen/headers/petsc.h
+++ b/doc/doxygen/headers/petsc.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2003 - 2022 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2006 - 2022 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 
diff --git a/doc/doxygen/headers/physics.h b/doc/doxygen/headers/physics.h
index ecade19602..cb7f5e05cd 100644
--- a/doc/doxygen/headers/physics.h
+++ b/doc/doxygen/headers/physics.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2016 - 2022 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @defgroup physics Physics
diff --git a/doc/doxygen/headers/polynomials.h b/doc/doxygen/headers/polynomials.h
index 6f4b12054c..ef8bcdcd12 100644
--- a/doc/doxygen/headers/polynomials.h
+++ b/doc/doxygen/headers/polynomials.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2005 - 2014 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2006 - 2014 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/preconditioners.h b/doc/doxygen/headers/preconditioners.h
index d2527efbfc..2f90859d13 100644
--- a/doc/doxygen/headers/preconditioners.h
+++ b/doc/doxygen/headers/preconditioners.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2003 - 2015 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2006 - 2015 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 
diff --git a/doc/doxygen/headers/quadrature.h b/doc/doxygen/headers/quadrature.h
index a1d28571d1..28dc91fd0b 100644
--- a/doc/doxygen/headers/quadrature.h
+++ b/doc/doxygen/headers/quadrature.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2005 - 2020 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/reordering.h b/doc/doxygen/headers/reordering.h
index ae376a2c15..f2e1559706 100644
--- a/doc/doxygen/headers/reordering.h
+++ b/doc/doxygen/headers/reordering.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2002 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @defgroup reordering Grid reordering and cell orientation
diff --git a/doc/doxygen/headers/simplex.h b/doc/doxygen/headers/simplex.h
index 5a137550b6..2e27b57e2b 100644
--- a/doc/doxygen/headers/simplex.h
+++ b/doc/doxygen/headers/simplex.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2020 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/slepc.h b/doc/doxygen/headers/slepc.h
index 1d470fed6d..7cd8b49456 100644
--- a/doc/doxygen/headers/slepc.h
+++ b/doc/doxygen/headers/slepc.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2011 - 2022 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 
diff --git a/doc/doxygen/headers/solvers.h b/doc/doxygen/headers/solvers.h
index 22a79b9b62..86a7a01371 100644
--- a/doc/doxygen/headers/solvers.h
+++ b/doc/doxygen/headers/solvers.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2003 - 2014 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2006 - 2014 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @defgroup Solvers Linear solver classes
diff --git a/doc/doxygen/headers/sparsity.h b/doc/doxygen/headers/sparsity.h
index 2cfcdb7139..3082d34ab0 100644
--- a/doc/doxygen/headers/sparsity.h
+++ b/doc/doxygen/headers/sparsity.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2003 - 2015 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2006 - 2015 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/trilinos.h b/doc/doxygen/headers/trilinos.h
index 3b02edcb0c..9dc5571f8f 100644
--- a/doc/doxygen/headers/trilinos.h
+++ b/doc/doxygen/headers/trilinos.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2008 - 2022 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 
diff --git a/doc/doxygen/headers/update_flags.h b/doc/doxygen/headers/update_flags.h
index a6e69247f8..87a8deb196 100644
--- a/doc/doxygen/headers/update_flags.h
+++ b/doc/doxygen/headers/update_flags.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2006 - 2022 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2007 - 2022 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/utilities.h b/doc/doxygen/headers/utilities.h
index 704cb39024..977e92d32e 100644
--- a/doc/doxygen/headers/utilities.h
+++ b/doc/doxygen/headers/utilities.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2006 - 2014 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/headers/vector_memory.h b/doc/doxygen/headers/vector_memory.h
index efa473c35f..afb433885d 100644
--- a/doc/doxygen/headers/vector_memory.h
+++ b/doc/doxygen/headers/vector_memory.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2003 - 2014 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2006 - 2014 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 
diff --git a/doc/doxygen/headers/vector_valued.h b/doc/doxygen/headers/vector_valued.h
index a65fe7df57..6dc497fdb7 100644
--- a/doc/doxygen/headers/vector_valued.h
+++ b/doc/doxygen/headers/vector_valued.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2008 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 
diff --git a/doc/doxygen/headers/vectors.h b/doc/doxygen/headers/vectors.h
index 0adbb87aeb..2cef93df2b 100644
--- a/doc/doxygen/headers/vectors.h
+++ b/doc/doxygen/headers/vectors.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
+// SPDX-License-Identifier: LGPL-2.1-or-later
 // Copyright (C) 2003 - 2015 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/doxygen/scripts/code-gallery.pl b/doc/doxygen/scripts/code-gallery.pl
index c864b04ae3..d7a4397e75 100644
--- a/doc/doxygen/scripts/code-gallery.pl
+++ b/doc/doxygen/scripts/code-gallery.pl
@@ -1,17 +1,16 @@
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 ##
+## SPDX-License-Identifier: LGPL-2.1-or-later
 ## Copyright (C) 2016 - 2018 by the deal.II authors
 ##
 ## This file is part of the deal.II library.
 ##
-## The deal.II library is free software; you can use it, redistribute
-## it, and/or modify it under the terms of the GNU Lesser General
-## Public License as published by the Free Software Foundation; either
-## version 2.1 of the License, or (at your option) any later version.
-## The full text of the license can be found in the file LICENSE.md at
-## the top level directory of deal.II.
+## Part of the source code is dual licensed under Apache-2.0 WITH
+## LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+## governing the source code and code contributions can be found in
+## LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 ##
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 
 use strict;
 
diff --git a/doc/doxygen/scripts/create_anchors.pl b/doc/doxygen/scripts/create_anchors.pl
index 5235b1d4bf..181e6022da 100644
--- a/doc/doxygen/scripts/create_anchors.pl
+++ b/doc/doxygen/scripts/create_anchors.pl
@@ -1,17 +1,16 @@
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 ##
+## SPDX-License-Identifier: LGPL-2.1-or-later
 ## Copyright (C) 2007 - 2023 by the deal.II authors
 ##
 ## This file is part of the deal.II library.
 ##
-## The deal.II library is free software; you can use it, redistribute
-## it, and/or modify it under the terms of the GNU Lesser General
-## Public License as published by the Free Software Foundation; either
-## version 2.1 of the License, or (at your option) any later version.
-## The full text of the license can be found in the file LICENSE.md at
-## the top level directory of deal.II.
+## Part of the source code is dual licensed under Apache-2.0 WITH
+## LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+## governing the source code and code contributions can be found in
+## LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 ##
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 
 
 # If we find a heading in a .dox file, create an HTML anchor for it.
diff --git a/doc/doxygen/scripts/filter.pl b/doc/doxygen/scripts/filter.pl
index 35565556a7..5cf4e59968 100755
--- a/doc/doxygen/scripts/filter.pl
+++ b/doc/doxygen/scripts/filter.pl
@@ -1,18 +1,17 @@
 #!/usr/bin/perl
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 ##
+## SPDX-License-Identifier: LGPL-2.1-or-later
 ## Copyright (C) 2007 - 2023 by the deal.II authors
 ##
 ## This file is part of the deal.II library.
 ##
-## The deal.II library is free software; you can use it, redistribute
-## it, and/or modify it under the terms of the GNU Lesser General
-## Public License as published by the Free Software Foundation; either
-## version 2.1 of the License, or (at your option) any later version.
-## The full text of the license can be found in the file LICENSE.md at
-## the top level directory of deal.II.
+## Part of the source code is dual licensed under Apache-2.0 WITH
+## LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+## governing the source code and code contributions can be found in
+## LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 ##
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 
 
 # read all lines of input. within the loop, first do some
diff --git a/doc/doxygen/scripts/intro2toc.pl b/doc/doxygen/scripts/intro2toc.pl
index d82bc2b975..9ebb27c3d3 100644
--- a/doc/doxygen/scripts/intro2toc.pl
+++ b/doc/doxygen/scripts/intro2toc.pl
@@ -1,17 +1,16 @@
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 ##
+## SPDX-License-Identifier: LGPL-2.1-or-later
 ## Copyright (C) 2006 - 2023 by the deal.II authors
 ##
 ## This file is part of the deal.II library.
 ##
-## The deal.II library is free software; you can use it, redistribute
-## it, and/or modify it under the terms of the GNU Lesser General
-## Public License as published by the Free Software Foundation; either
-## version 2.1 of the License, or (at your option) any later version.
-## The full text of the license can be found in the file LICENSE.md at
-## the top level directory of deal.II.
+## Part of the source code is dual licensed under Apache-2.0 WITH
+## LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+## governing the source code and code contributions can be found in
+## LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 ##
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 
 print "    <ul>\n";
 use Getopt::Long;
diff --git a/doc/doxygen/scripts/make_gallery.pl b/doc/doxygen/scripts/make_gallery.pl
index de8120a71e..50ae0d7fa7 100644
--- a/doc/doxygen/scripts/make_gallery.pl
+++ b/doc/doxygen/scripts/make_gallery.pl
@@ -1,17 +1,16 @@
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 ##
+## SPDX-License-Identifier: LGPL-2.1-or-later
 ## Copyright (C) 2013 - 2023 by the deal.II authors
 ##
 ## This file is part of the deal.II library.
 ##
-## The deal.II library is free software; you can use it, redistribute
-## it, and/or modify it under the terms of the GNU Lesser General
-## Public License as published by the Free Software Foundation; either
-## version 2.1 of the License, or (at your option) any later version.
-## The full text of the license can be found in the file LICENSE.md at
-## the top level directory of deal.II.
+## Part of the source code is dual licensed under Apache-2.0 WITH
+## LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+## governing the source code and code contributions can be found in
+## LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 ##
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 
 if ($#ARGV < 1) {
   print "\nUsage: make_gallery.pl cmake_source_dir gallery_name gallery_dir gallery_src_files...\n";
diff --git a/doc/doxygen/scripts/make_step.pl b/doc/doxygen/scripts/make_step.pl
index 329fd47832..8cc9b66dfb 100644
--- a/doc/doxygen/scripts/make_step.pl
+++ b/doc/doxygen/scripts/make_step.pl
@@ -1,17 +1,16 @@
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 ##
+## SPDX-License-Identifier: LGPL-2.1-or-later
 ## Copyright (C) 2013 - 2023 by the deal.II authors
 ##
 ## This file is part of the deal.II library.
 ##
-## The deal.II library is free software; you can use it, redistribute
-## it, and/or modify it under the terms of the GNU Lesser General
-## Public License as published by the Free Software Foundation; either
-## version 2.1 of the License, or (at your option) any later version.
-## The full text of the license can be found in the file LICENSE.md at
-## the top level directory of deal.II.
+## Part of the source code is dual licensed under Apache-2.0 WITH
+## LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+## governing the source code and code contributions can be found in
+## LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 ##
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 
 if ($#ARGV != 1) {
   print "\nUsage: make_step.pl step cmake_source_dir\n";
diff --git a/doc/doxygen/scripts/mod_header.pl.in b/doc/doxygen/scripts/mod_header.pl.in
index dc45c51b0f..9916ace142 100644
--- a/doc/doxygen/scripts/mod_header.pl.in
+++ b/doc/doxygen/scripts/mod_header.pl.in
@@ -1,17 +1,16 @@
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 ##
-## Copyright (C) 2014 - 2018 by the deal.II authors
+## SPDX-License-Identifier: LGPL-2.1-or-later
+## Copyright (C) 2014 - 2020 by the deal.II authors
 ##
 ## This file is part of the deal.II library.
 ##
-## The deal.II library is free software; you can use it, redistribute
-## it, and/or modify it under the terms of the GNU Lesser General
-## Public License as published by the Free Software Foundation; either
-## version 2.1 of the License, or (at your option) any later version.
-## The full text of the license can be found in the file LICENSE.md at
-## the top level directory of deal.II.
+## Part of the source code is dual licensed under Apache-2.0 WITH
+## LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+## governing the source code and code contributions can be found in
+## LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 ##
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 
 #
 # A PERL script that modifies the default-generated 'header.html' file
diff --git a/doc/doxygen/scripts/program2doxygen.pl b/doc/doxygen/scripts/program2doxygen.pl
index e7115506c6..2b500c2022 100644
--- a/doc/doxygen/scripts/program2doxygen.pl
+++ b/doc/doxygen/scripts/program2doxygen.pl
@@ -1,17 +1,16 @@
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 ##
+## SPDX-License-Identifier: LGPL-2.1-or-later
 ## Copyright (C) 2006 - 2023 by the deal.II authors
 ##
 ## This file is part of the deal.II library.
 ##
-## The deal.II library is free software; you can use it, redistribute
-## it, and/or modify it under the terms of the GNU Lesser General
-## Public License as published by the Free Software Foundation; either
-## version 2.1 of the License, or (at your option) any later version.
-## The full text of the license can be found in the file LICENSE.md at
-## the top level directory of deal.II.
+## Part of the source code is dual licensed under Apache-2.0 WITH
+## LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+## governing the source code and code contributions can be found in
+## LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 ##
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 
 
 # Skip header lines at the top of the file, such as copyright notices and
diff --git a/doc/doxygen/scripts/program2html.pl b/doc/doxygen/scripts/program2html.pl
index 3abbd8ea75..50371a468d 100644
--- a/doc/doxygen/scripts/program2html.pl
+++ b/doc/doxygen/scripts/program2html.pl
@@ -1,17 +1,16 @@
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 ##
+## SPDX-License-Identifier: LGPL-2.1-or-later
 ## Copyright (C) 2006 - 2023 by the deal.II authors
 ##
 ## This file is part of the deal.II library.
 ##
-## The deal.II library is free software; you can use it, redistribute
-## it, and/or modify it under the terms of the GNU Lesser General
-## Public License as published by the Free Software Foundation; either
-## version 2.1 of the License, or (at your option) any later version.
-## The full text of the license can be found in the file LICENSE.md at
-## the top level directory of deal.II.
+## Part of the source code is dual licensed under Apache-2.0 WITH
+## LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+## governing the source code and code contributions can be found in
+## LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 ##
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 
 print "<a name=\"CommProg\"></a>\n";
 print "<h1> The commented program</h1>\n";
diff --git a/doc/doxygen/scripts/program2plain.pl b/doc/doxygen/scripts/program2plain.pl
index d28992d7e8..62502650d9 100644
--- a/doc/doxygen/scripts/program2plain.pl
+++ b/doc/doxygen/scripts/program2plain.pl
@@ -1,17 +1,16 @@
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 ##
+## SPDX-License-Identifier: LGPL-2.1-or-later
 ## Copyright (C) 2010 - 2023 by the deal.II authors
 ##
 ## This file is part of the deal.II library.
 ##
-## The deal.II library is free software; you can use it, redistribute
-## it, and/or modify it under the terms of the GNU Lesser General
-## Public License as published by the Free Software Foundation; either
-## version 2.1 of the License, or (at your option) any later version.
-## The full text of the license can be found in the file LICENSE.md at
-## the top level directory of deal.II.
+## Part of the source code is dual licensed under Apache-2.0 WITH
+## LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+## governing the source code and code contributions can be found in
+## LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 ##
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 
 # Remove all comments from the source file
 
diff --git a/doc/doxygen/scripts/program2toc.pl b/doc/doxygen/scripts/program2toc.pl
index 4ef53b25b4..0c684924b0 100644
--- a/doc/doxygen/scripts/program2toc.pl
+++ b/doc/doxygen/scripts/program2toc.pl
@@ -1,17 +1,16 @@
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 ##
+## SPDX-License-Identifier: LGPL-2.1-or-later
 ## Copyright (C) 2006 - 2023 by the deal.II authors
 ##
 ## This file is part of the deal.II library.
 ##
-## The deal.II library is free software; you can use it, redistribute
-## it, and/or modify it under the terms of the GNU Lesser General
-## Public License as published by the Free Software Foundation; either
-## version 2.1 of the License, or (at your option) any later version.
-## The full text of the license can be found in the file LICENSE.md at
-## the top level directory of deal.II.
+## Part of the source code is dual licensed under Apache-2.0 WITH
+## LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+## governing the source code and code contributions can be found in
+## LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 ##
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 
 print "    <ul>\n";
 use Getopt::Long;
diff --git a/doc/doxygen/scripts/set_canonical_doxygen.pl b/doc/doxygen/scripts/set_canonical_doxygen.pl
index 8b3a6e8928..055be4f61a 100644
--- a/doc/doxygen/scripts/set_canonical_doxygen.pl
+++ b/doc/doxygen/scripts/set_canonical_doxygen.pl
@@ -1,17 +1,16 @@
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 ##
+## SPDX-License-Identifier: LGPL-2.1-or-later
 ## Copyright (C) 2019 by the deal.II authors
 ##
 ## This file is part of the deal.II library.
 ##
-## The deal.II library is free software; you can use it, redistribute
-## it, and/or modify it under the terms of the GNU Lesser General
-## Public License as published by the Free Software Foundation; either
-## version 2.1 of the License, or (at your option) any later version.
-## The full text of the license can be found in the file LICENSE at
-## the top level of the deal.II distribution.
+## Part of the source code is dual licensed under Apache-2.0 WITH
+## LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+## governing the source code and code contributions can be found in
+## LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 ##
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 
 # This script sets the canonical webpage for all the webpages of the
 # doxygen documentation. For more information see
diff --git a/doc/doxygen/scripts/steps.pl b/doc/doxygen/scripts/steps.pl
index e2d1808cc2..3b19bb0c82 100644
--- a/doc/doxygen/scripts/steps.pl
+++ b/doc/doxygen/scripts/steps.pl
@@ -1,17 +1,16 @@
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 ##
-## Copyright (C) 2006 - 2023 by the deal.II authors
+## SPDX-License-Identifier: LGPL-2.1-or-later
+## Copyright (C) 2009 - 2023 by the deal.II authors
 ##
 ## This file is part of the deal.II library.
 ##
-## The deal.II library is free software; you can use it, redistribute
-## it, and/or modify it under the terms of the GNU Lesser General
-## Public License as published by the Free Software Foundation; either
-## version 2.1 of the License, or (at your option) any later version.
-## The full text of the license can be found in the file LICENSE.md at
-## the top level directory of deal.II.
+## Part of the source code is dual licensed under Apache-2.0 WITH
+## LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+## governing the source code and code contributions can be found in
+## LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 ##
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 
 use strict;
 
diff --git a/doc/doxygen/scripts/validate-xrefs.pl b/doc/doxygen/scripts/validate-xrefs.pl
index cccaea67e2..338f322514 100644
--- a/doc/doxygen/scripts/validate-xrefs.pl
+++ b/doc/doxygen/scripts/validate-xrefs.pl
@@ -1,17 +1,16 @@
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 ##
+## SPDX-License-Identifier: LGPL-2.1-or-later
 ## Copyright (C) 2006 - 2023 by the deal.II authors
 ##
 ## This file is part of the deal.II library.
 ##
-## The deal.II library is free software; you can use it, redistribute
-## it, and/or modify it under the terms of the GNU Lesser General
-## Public License as published by the Free Software Foundation; either
-## version 2.1 of the License, or (at your option) any later version.
-## The full text of the license can be found in the file LICENSE.md at
-## the top level directory of deal.II.
+## Part of the source code is dual licensed under Apache-2.0 WITH
+## LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+## governing the source code and code contributions can be found in
+## LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 ##
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 
 #
 # Author: Wolfgang Bangerth, Guido Kanschat 2000, 2004
diff --git a/doc/doxygen/tutorial/CMakeLists.txt b/doc/doxygen/tutorial/CMakeLists.txt
index e324651b65..cf508027ec 100644
--- a/doc/doxygen/tutorial/CMakeLists.txt
+++ b/doc/doxygen/tutorial/CMakeLists.txt
@@ -1,17 +1,15 @@
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 ##
 ## Copyright (C) 2012 - 2023 by the deal.II Authors
 ##
 ## This file is part of the deal.II library.
 ##
-## The deal.II library is free software; you can use it, redistribute
-## it, and/or modify it under the terms of the GNU Lesser General
-## Public License as published by the Free Software Foundation; either
-## version 2.1 of the License, or (at your option) any later version.
-## The full text of the license can be found in the file LICENSE.md at
-## the top level directory of deal.II.
+## Part of the source code is dual licensed under Apache-2.0 WITH
+## LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+## governing the source code and code contributions can be found in
+## LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 ##
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 
 
 
diff --git a/doc/doxygen/tutorial/tutorial.h.in b/doc/doxygen/tutorial/tutorial.h.in
index d11fa7d2ed..c32a84429e 100644
--- a/doc/doxygen/tutorial/tutorial.h.in
+++ b/doc/doxygen/tutorial/tutorial.h.in
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2005 - 2023 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2013 - 2024 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 
 /**
diff --git a/doc/external-libs/p4est-setup.sh b/doc/external-libs/p4est-setup.sh
index 9c2bbc45fa..c15d1e4011 100755
--- a/doc/external-libs/p4est-setup.sh
+++ b/doc/external-libs/p4est-setup.sh
@@ -1,5 +1,7 @@
 #! /bin/bash
 #
+# SPDX-License-Identifier: GPL-2.0-or-later
+#
 # This file is part of p4est [1].
 # p4est is a C library to manage a collection (a forest) of multiple
 # connected adaptive quadtrees or octrees in parallel.
diff --git a/doc/news/1.0.0-vs-2.0.0.h b/doc/news/1.0.0-vs-2.0.0.h
index aa1d9a33f2..0f00368328 100644
--- a/doc/news/1.0.0-vs-2.0.0.h
+++ b/doc/news/1.0.0-vs-2.0.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2013, 2014 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2014 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @page changes_between_1_0_and_2_0 Changes between Version 1.0 and 2.0
diff --git a/doc/news/2.0.0-vs-3.0.0.h b/doc/news/2.0.0-vs-3.0.0.h
index 7e0a693b63..945b079f86 100644
--- a/doc/news/2.0.0-vs-3.0.0.h
+++ b/doc/news/2.0.0-vs-3.0.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2013, 2014 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2013 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @page changes_between_2_0_and_3_0 Changes between Version 2.0 and 3.0
diff --git a/doc/news/3.0.0-vs-3.0.1.h b/doc/news/3.0.0-vs-3.0.1.h
index c2e75f695a..e4243b71af 100644
--- a/doc/news/3.0.0-vs-3.0.1.h
+++ b/doc/news/3.0.0-vs-3.0.1.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2013, 2014 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2013 - 2020 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @page changes_between_3_0_0_and_3_0_1 Changes between Version 3.0.0 and 3.0.1
diff --git a/doc/news/3.0.0-vs-3.1.0.h b/doc/news/3.0.0-vs-3.1.0.h
index e00c6254af..d673e1af26 100644
--- a/doc/news/3.0.0-vs-3.1.0.h
+++ b/doc/news/3.0.0-vs-3.1.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2013, 2014 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2013 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @page changes_between_3_0_0_and_3_1_0 Changes between Version 3.0.0 and 3.1.0
diff --git a/doc/news/3.1.0-vs-3.1.1.h b/doc/news/3.1.0-vs-3.1.1.h
index 8567aa77e0..5b4e7ca32f 100644
--- a/doc/news/3.1.0-vs-3.1.1.h
+++ b/doc/news/3.1.0-vs-3.1.1.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2013, 2014 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2013 - 2020 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @page changes_between_3_1_0_and_3_1_1 Changes between Version 3.1.0 and 3.1.1
diff --git a/doc/news/3.1.0-vs-3.2.0.h b/doc/news/3.1.0-vs-3.2.0.h
index d9f4811d15..9b230ef92d 100644
--- a/doc/news/3.1.0-vs-3.2.0.h
+++ b/doc/news/3.1.0-vs-3.2.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2013, 2014 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2013 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @page changes_between_3_1_0_and_3_2_0 Changes between Version 3.1.0 and 3.2.0
diff --git a/doc/news/3.1.1-vs-3.1.2.h b/doc/news/3.1.1-vs-3.1.2.h
index 09709b6d20..ade16a8f50 100644
--- a/doc/news/3.1.1-vs-3.1.2.h
+++ b/doc/news/3.1.1-vs-3.1.2.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2013, 2014 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2014 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @page changes_between_3_1_1_and_3_1_2 Changes between Version 3.1.1 and 3.1.2
diff --git a/doc/news/3.2.0-vs-3.2.1.h b/doc/news/3.2.0-vs-3.2.1.h
index cf8316d263..12e6e12c63 100644
--- a/doc/news/3.2.0-vs-3.2.1.h
+++ b/doc/news/3.2.0-vs-3.2.1.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2013, 2014 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2013 - 2020 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @page changes_between_3_2_0_and_3_2_1 Changes between Version 3.2.0 and 3.2.1
diff --git a/doc/news/3.2.0-vs-3.3.0.h b/doc/news/3.2.0-vs-3.3.0.h
index 1e6f80baaa..bd83561c4c 100644
--- a/doc/news/3.2.0-vs-3.3.0.h
+++ b/doc/news/3.2.0-vs-3.3.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2013, 2014 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2013 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @page changes_between_3_2_and_3_3 Changes between Version 3.2 and 3.3
diff --git a/doc/news/3.3.0-vs-3.3.1.h b/doc/news/3.3.0-vs-3.3.1.h
index 0461dd1657..787c55c6e5 100644
--- a/doc/news/3.3.0-vs-3.3.1.h
+++ b/doc/news/3.3.0-vs-3.3.1.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2013, 2014 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2014 - 2020 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @page changes_between_3_3_0_and_3_3_1 Changes between Version 3.3.0 and 3.3.1
diff --git a/doc/news/3.3.0-vs-3.4.0.h b/doc/news/3.3.0-vs-3.4.0.h
index fc459394c2..07429763a3 100644
--- a/doc/news/3.3.0-vs-3.4.0.h
+++ b/doc/news/3.3.0-vs-3.4.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2013, 2014 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2013 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @page changes_between_3_3_and_3_4 Changes between Version 3.3 and 3.4
diff --git a/doc/news/3.4.0-vs-4.0.0.h b/doc/news/3.4.0-vs-4.0.0.h
index 0c6db20aea..c28e936d59 100644
--- a/doc/news/3.4.0-vs-4.0.0.h
+++ b/doc/news/3.4.0-vs-4.0.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2013, 2014 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2013 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @page changes_between_3_4_and_4_0 Changes between Version 3.4 and 4.0
diff --git a/doc/news/4.0.0-vs-5.0.0.h b/doc/news/4.0.0-vs-5.0.0.h
index 0bce879293..4cd420ac86 100644
--- a/doc/news/4.0.0-vs-5.0.0.h
+++ b/doc/news/4.0.0-vs-5.0.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2013, 2014 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2013 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @page changes_between_4_0_and_5_0 Changes between Version 4.0 and 5.0
diff --git a/doc/news/5.0.0-vs-5.1.0.h b/doc/news/5.0.0-vs-5.1.0.h
index 9bd3509059..645a923ddb 100644
--- a/doc/news/5.0.0-vs-5.1.0.h
+++ b/doc/news/5.0.0-vs-5.1.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2013, 2014 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2013 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @page changes_between_5_0_and_5_1 Changes between Version 5.0 and 5.1
diff --git a/doc/news/5.1.0-vs-5.2.0.h b/doc/news/5.1.0-vs-5.2.0.h
index 6a16c0e06f..7375b08ce3 100644
--- a/doc/news/5.1.0-vs-5.2.0.h
+++ b/doc/news/5.1.0-vs-5.2.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2013, 2014 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2013 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @page changes_between_5_1_and_5_2 Changes between Version 5.1 and 5.2
diff --git a/doc/news/5.2.0-vs-6.0.0.h b/doc/news/5.2.0-vs-6.0.0.h
index 9c8f035253..689028cd25 100644
--- a/doc/news/5.2.0-vs-6.0.0.h
+++ b/doc/news/5.2.0-vs-6.0.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2013, 2014 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2013 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @page changes_between_5_2_and_6_0 Changes between Version 5.2 and 6.0
diff --git a/doc/news/6.0.0-vs-6.1.0.h b/doc/news/6.0.0-vs-6.1.0.h
index 496c2cf061..3e475b546a 100644
--- a/doc/news/6.0.0-vs-6.1.0.h
+++ b/doc/news/6.0.0-vs-6.1.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2007 - 2013 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2007 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @page changes_between_6_0_and_6_1 Changes between Version 6.0 and 6.1
diff --git a/doc/news/6.1.0-vs-6.2.0.h b/doc/news/6.1.0-vs-6.2.0.h
index fd7e5e16a7..29ea5018db 100644
--- a/doc/news/6.1.0-vs-6.2.0.h
+++ b/doc/news/6.1.0-vs-6.2.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2009 - 2013 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2009 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @page changes_between_6_1_and_6_2 Changes between Version 6.1 and 6.2
diff --git a/doc/news/6.2.0-vs-6.2.1.h b/doc/news/6.2.0-vs-6.2.1.h
index 5a772e1723..114e683a5c 100644
--- a/doc/news/6.2.0-vs-6.2.1.h
+++ b/doc/news/6.2.0-vs-6.2.1.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2009 - 2013 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2009 - 2014 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @page changes_between_6_2_0_and_6_2_1 Changes between Version 6.2.0 and 6.2.1
diff --git a/doc/news/6.2.0-vs-6.3.0.h b/doc/news/6.2.0-vs-6.3.0.h
index f67e69df91..34fbca1def 100644
--- a/doc/news/6.2.0-vs-6.3.0.h
+++ b/doc/news/6.2.0-vs-6.3.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2010 - 2013 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2010 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @page changes_between_6_2_and_6_3 Changes between Version 6.2 and 6.3
diff --git a/doc/news/6.3.0-vs-6.3.1.h b/doc/news/6.3.0-vs-6.3.1.h
index d43a7fe0fc..c4ff794ccb 100644
--- a/doc/news/6.3.0-vs-6.3.1.h
+++ b/doc/news/6.3.0-vs-6.3.1.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2010 - 2013 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2010 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @page changes_between_6_3_0_and_6_3_1 Changes between Version 6.3.0 and 6.3.1
diff --git a/doc/news/6.3.0-vs-7.0.0.h b/doc/news/6.3.0-vs-7.0.0.h
index c1da53e90b..b10f8b18bd 100644
--- a/doc/news/6.3.0-vs-7.0.0.h
+++ b/doc/news/6.3.0-vs-7.0.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2011 - 2013 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2011 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @page changes_between_6_3_and_7_0 Changes between Version 6.3 and 7.0
diff --git a/doc/news/7.0.0-vs-7.1.0.h b/doc/news/7.0.0-vs-7.1.0.h
index f84132e4e2..848a28d81f 100644
--- a/doc/news/7.0.0-vs-7.1.0.h
+++ b/doc/news/7.0.0-vs-7.1.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2011 - 2013 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2011 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @page changes_between_7_0_and_7_1 Changes between Version 7.0 and 7.1
diff --git a/doc/news/7.1.0-vs-7.2.0.h b/doc/news/7.1.0-vs-7.2.0.h
index 8ec5ad406a..16aa6e3e11 100644
--- a/doc/news/7.1.0-vs-7.2.0.h
+++ b/doc/news/7.1.0-vs-7.2.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2012 - 2013 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2012 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @page changes_between_7_1_and_7_2 Changes between Version 7.1 and 7.2
diff --git a/doc/news/7.2.0-vs-7.3.0.h b/doc/news/7.2.0-vs-7.3.0.h
index 91db34b5e3..4cfd493b2a 100644
--- a/doc/news/7.2.0-vs-7.3.0.h
+++ b/doc/news/7.2.0-vs-7.3.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2013 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2013 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @page changes_between_7_2_and_7_3 Changes between Version 7.2 and 7.3
diff --git a/doc/news/7.3.0-vs-8.0.0.h b/doc/news/7.3.0-vs-8.0.0.h
index 847d80c16c..233b5d5804 100644
--- a/doc/news/7.3.0-vs-8.0.0.h
+++ b/doc/news/7.3.0-vs-8.0.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2013 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2013 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @page changes_between_7_3_and_8_0 Changes between Version 7.3 and 8.0
diff --git a/doc/news/8.0.0-vs-8.1.0.h b/doc/news/8.0.0-vs-8.1.0.h
index f0caf23793..6eaf100894 100644
--- a/doc/news/8.0.0-vs-8.1.0.h
+++ b/doc/news/8.0.0-vs-8.1.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2013 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2013 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @page changes_between_8_0_and_8_1 Changes between Version 8.0 and 8.1
diff --git a/doc/news/8.1.0-vs-8.2.0.h b/doc/news/8.1.0-vs-8.2.0.h
index f69faa0b2b..708f8e840d 100644
--- a/doc/news/8.1.0-vs-8.2.0.h
+++ b/doc/news/8.1.0-vs-8.2.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2013 - 2014, 2014 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2013 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
 @page changes_between_8_1_and_8_2 Changes between Version 8.1 and 8.2
diff --git a/doc/news/8.2.0-vs-8.2.1.h b/doc/news/8.2.0-vs-8.2.1.h
index 95349e03fb..fcdf59361c 100644
--- a/doc/news/8.2.0-vs-8.2.1.h
+++ b/doc/news/8.2.0-vs-8.2.1.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2014 - 2015 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2015 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
 @page changes_between_8_2_0_and_8_2_1 Changes between Version 8.2.0 and 8.2.1
diff --git a/doc/news/8.2.1-vs-8.3.0.h b/doc/news/8.2.1-vs-8.3.0.h
index ddf6b79e85..03e7d7968d 100644
--- a/doc/news/8.2.1-vs-8.3.0.h
+++ b/doc/news/8.2.1-vs-8.3.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2014 - 2015 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2014 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
  * @page changes_between_8_2_1_and_8_3 Changes between Version 8.2.1 and 8.3
diff --git a/doc/news/8.3.0-vs-8.4.0.h b/doc/news/8.3.0-vs-8.4.0.h
index cb751ff197..9313af18e8 100644
--- a/doc/news/8.3.0-vs-8.4.0.h
+++ b/doc/news/8.3.0-vs-8.4.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2014 - 2016 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2014 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
 @page changes_between_8_3_and_8_4 Changes between Version 8.3.0 and 8.4.0
diff --git a/doc/news/8.4.0-vs-8.4.1.h b/doc/news/8.4.0-vs-8.4.1.h
index eaa44889cd..1c4f8e35a1 100644
--- a/doc/news/8.4.0-vs-8.4.1.h
+++ b/doc/news/8.4.0-vs-8.4.1.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2014 - 2016 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2015 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
 @page changes_between_8_4_0_and_8_4_1 Changes between Version 8.4.0 and 8.4.1
diff --git a/doc/news/8.4.1-vs-8.4.2.h b/doc/news/8.4.1-vs-8.4.2.h
index 05372f543c..27282b8d02 100644
--- a/doc/news/8.4.1-vs-8.4.2.h
+++ b/doc/news/8.4.1-vs-8.4.2.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2014 - 2016 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2015 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
 @page changes_between_8_4_1_and_8_4_2 Changes between Version 8.4.1 and 8.4.2
diff --git a/doc/news/8.4.2-vs-8.5.0.h b/doc/news/8.4.2-vs-8.5.0.h
index 659a19c94e..d8df61dab6 100644
--- a/doc/news/8.4.2-vs-8.5.0.h
+++ b/doc/news/8.4.2-vs-8.5.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2017 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2017 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
 @page changes_between_8_4_2_and_8_5_0 Changes between Version 8.4.2 and 8.5.0
diff --git a/doc/news/8.5.0-vs-9.0.0.h b/doc/news/8.5.0-vs-9.0.0.h
index 9ca82ec8ac..b349969de9 100644
--- a/doc/news/8.5.0-vs-9.0.0.h
+++ b/doc/news/8.5.0-vs-9.0.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2017 - 2018 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2018 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
 @page changes_between_8_5_0_and_9_0_0 Changes between Version 8.5.0 and 9.0.0
diff --git a/doc/news/9.0.0-vs-9.0.1.h b/doc/news/9.0.0-vs-9.0.1.h
index 72a75543b1..1884ec9e27 100644
--- a/doc/news/9.0.0-vs-9.0.1.h
+++ b/doc/news/9.0.0-vs-9.0.1.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2017 - 2018 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2018 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE at
-// the top level of the deal.II distribution.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
 @page changes_between_9_0_0_and_9_0_1 Changes between Version 9.0.0 and 9.0.1
diff --git a/doc/news/9.0.1-vs-9.1.0.h b/doc/news/9.0.1-vs-9.1.0.h
index 1b5ae7ca1d..5940ddcc21 100644
--- a/doc/news/9.0.1-vs-9.1.0.h
+++ b/doc/news/9.0.1-vs-9.1.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2017 - 2019 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2019 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
 @page changes_between_9_0_1_and_9_1_0 Changes between Version 9.0.1 and 9.1.0
diff --git a/doc/news/9.1.0-vs-9.1.1.h b/doc/news/9.1.0-vs-9.1.1.h
index 0f6fd01f1c..26301fa285 100644
--- a/doc/news/9.1.0-vs-9.1.1.h
+++ b/doc/news/9.1.0-vs-9.1.1.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2017 - 2019 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2017 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
 @page changes_between_9_1_0_and_9_1_1 Changes between Version 9.1.0 and 9.1.1
diff --git a/doc/news/9.1.1-vs-9.2.0.h b/doc/news/9.1.1-vs-9.2.0.h
index 59c8f5761c..b4075c1ab4 100644
--- a/doc/news/9.1.1-vs-9.2.0.h
+++ b/doc/news/9.1.1-vs-9.2.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2019 - 2020 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2020 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
 @page changes_between_9_1_1_and_9_2_0 Changes between Version 9.1.1 and 9.2.0
diff --git a/doc/news/9.2.0-vs-9.3.0.h b/doc/news/9.2.0-vs-9.3.0.h
index b17879e2b8..4019f155d9 100644
--- a/doc/news/9.2.0-vs-9.3.0.h
+++ b/doc/news/9.2.0-vs-9.3.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2017 - 2021 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2021 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
 @page changes_between_9_2_0_and_9_3_0 Changes between Version 9.2.0 and 9.3.0
diff --git a/doc/news/9.3.0-vs-9.3.1.h b/doc/news/9.3.0-vs-9.3.1.h
index 8bedbf622a..2a9f5e8d5e 100644
--- a/doc/news/9.3.0-vs-9.3.1.h
+++ b/doc/news/9.3.0-vs-9.3.1.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2017 - 2021 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2021 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
 @page changes_between_9_3_0_and_9_3_1 Changes between Version 9.3.0 and 9.3.1
diff --git a/doc/news/9.3.1-vs-9.3.2.h b/doc/news/9.3.1-vs-9.3.2.h
index 49bee89d99..8a98be159d 100644
--- a/doc/news/9.3.1-vs-9.3.2.h
+++ b/doc/news/9.3.1-vs-9.3.2.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2017 - 2021 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2017 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
 @page changes_between_9_3_1_and_9_3_2 Changes between Version 9.3.1 and 9.3.2
diff --git a/doc/news/9.3.2-vs-9.3.3.h b/doc/news/9.3.2-vs-9.3.3.h
index 4df7ed4d1e..198d0db834 100644
--- a/doc/news/9.3.2-vs-9.3.3.h
+++ b/doc/news/9.3.2-vs-9.3.3.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2017 - 2022 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2022 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
 @page changes_between_9_3_2_and_9_3_3 Changes between Version 9.3.2 and 9.3.3
diff --git a/doc/news/9.3.3-vs-9.4.0.h b/doc/news/9.3.3-vs-9.4.0.h
index f42b1f66e9..3ba77d5254 100644
--- a/doc/news/9.3.3-vs-9.4.0.h
+++ b/doc/news/9.3.3-vs-9.4.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2017 - 2022 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2022 - 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
 @page changes_between_9_3_3_and_9_4_0 Changes between Version 9.3.3 and 9.4.0
diff --git a/doc/news/9.4.0-vs-9.5.0.h b/doc/news/9.4.0-vs-9.5.0.h
index 8ec0af6370..abdd443ca1 100644
--- a/doc/news/9.4.0-vs-9.5.0.h
+++ b/doc/news/9.4.0-vs-9.5.0.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2017 - 2023 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2023 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
 @page changes_between_9_4_0_and_9_5_0 Changes between Version 9.4.0 and 9.5.0
diff --git a/doc/news/9.5.0-vs-9.5.2.h b/doc/news/9.5.0-vs-9.5.2.h
index 0724868dc5..1ed05d3e05 100644
--- a/doc/news/9.5.0-vs-9.5.2.h
+++ b/doc/news/9.5.0-vs-9.5.2.h
@@ -1,17 +1,16 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2017 - 2023 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2024 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 
 /**
 @page changes_between_9_5_0_and_9_5_2 Changes between Version 9.5.0 and 9.5.2
diff --git a/doc/news/CMakeLists.txt b/doc/news/CMakeLists.txt
index a3883db4de..1610c1bc27 100644
--- a/doc/news/CMakeLists.txt
+++ b/doc/news/CMakeLists.txt
@@ -1,17 +1,15 @@
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 ##
 ## Copyright (C) 2016 - 2022 by the deal.II Authors
 ##
 ## This file is part of the deal.II library.
 ##
-## The deal.II library is free software; you can use it, redistribute
-## it, and/or modify it under the terms of the GNU Lesser General
-## Public License as published by the Free Software Foundation; either
-## version 2.1 of the License, or (at your option) any later version.
-## The full text of the license can be found in the file LICENSE.md at
-## the top level directory of deal.II.
+## Part of the source code is dual licensed under Apache-2.0 WITH
+## LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+## governing the source code and code contributions can be found in
+## LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 ##
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 
 
 #
diff --git a/doc/news/changes/create_changes_h.cmake b/doc/news/changes/create_changes_h.cmake
index b36d54a762..c8d7b84f4d 100644
--- a/doc/news/changes/create_changes_h.cmake
+++ b/doc/news/changes/create_changes_h.cmake
@@ -1,17 +1,15 @@
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 ##
 ## Copyright (C) 2016 - 2022 by the deal.II Authors
 ##
 ## This file is part of the deal.II library.
 ##
-## The deal.II library is free software; you can use it, redistribute
-## it, and/or modify it under the terms of the GNU Lesser General
-## Public License as published by the Free Software Foundation; either
-## version 2.1 of the License, or (at your option) any later version.
-## The full text of the license can be found in the file LICENSE.md at
-## the top level directory of deal.II.
+## Part of the source code is dual licensed under Apache-2.0 WITH
+## LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+## governing the source code and code contributions can be found in
+## LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 ##
-## ---------------------------------------------------------------------
+## ------------------------------------------------------------------------
 
 # Auxiliary functions
 function(cat IN_FILE OUT_FILE INDENT)
diff --git a/doc/news/changes/header b/doc/news/changes/header
index 31c66c89bf..66f026c95e 100644
--- a/doc/news/changes/header
+++ b/doc/news/changes/header
@@ -1,17 +1,17 @@
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// Copyright (C) 2017 - 2022 by the deal.II authors
+// SPDX-License-Identifier: LGPL-2.1-or-later
+// Copyright (C) 2016 - 2021 by the deal.II authors
 //
 // This file is part of the deal.II library.
 //
-// The deal.II library is free software; you can use it, redistribute
-// it, and/or modify it under the terms of the GNU Lesser General
-// Public License as published by the Free Software Foundation; either
-// version 2.1 of the License, or (at your option) any later version.
-// The full text of the license can be found in the file LICENSE.md at
-// the top level directory of deal.II.
+// Part of the source code is dual licensed under Apache-2.0 WITH
+// LLVM-exception OR LGPL-2.1-or-later. Detailed license information
+// governing the source code and code contributions can be found in
+// LICENSE.md and CONTRIBUTING.md at the top level directory of deal.II.
 //
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
+
 
 /**
 @page recent_changes Changes since the last release