From 3636b27dec0cfa80483c062ab0137964c40d50a3 Mon Sep 17 00:00:00 2001 From: Matthias Maier Date: Wed, 21 Feb 2024 02:02:51 -0600 Subject: [PATCH] Update license headers: ./doc --- doc/CMakeLists.txt | 14 ++++++-------- doc/developers/testsuite.html | 17 ++++++++--------- doc/doxygen/CMakeLists.txt | 15 +++++++-------- doc/doxygen/code-gallery/CMakeLists.txt | 14 ++++++-------- doc/doxygen/code-gallery/code-gallery.h.in | 15 +++++++-------- doc/doxygen/code-gallery/no-code-gallery.h | 15 +++++++-------- doc/doxygen/extra.sty | 19 +++++++++---------- .../automatic_and_symbolic_differentiation.h | 15 +++++++-------- doc/doxygen/headers/c++.h | 17 ++++++++--------- doc/doxygen/headers/coding_conventions.h | 17 ++++++++--------- doc/doxygen/headers/concepts.h | 15 +++++++-------- doc/doxygen/headers/constraints.h | 15 +++++++-------- doc/doxygen/headers/cuda.h | 15 +++++++-------- doc/doxygen/headers/distributed.h | 17 ++++++++--------- doc/doxygen/headers/dofs.h | 17 ++++++++--------- doc/doxygen/headers/exceptions.h | 15 +++++++-------- doc/doxygen/headers/fe.h | 17 ++++++++--------- .../headers/fe_vs_mapping_vs_fevalues.h | 15 +++++++-------- doc/doxygen/headers/functions.h | 15 +++++++-------- doc/doxygen/headers/geodynamics.h | 15 +++++++-------- doc/doxygen/headers/geometry_and_primitives.h | 15 +++++++-------- doc/doxygen/headers/global_dof_index.h | 15 +++++++-------- doc/doxygen/headers/glossary.h | 15 +++++++-------- doc/doxygen/headers/grid.h | 17 ++++++++--------- doc/doxygen/headers/hp.h | 15 +++++++-------- doc/doxygen/headers/instantiations.h | 15 +++++++-------- doc/doxygen/headers/integrators.h | 15 +++++++-------- doc/doxygen/headers/io.h | 17 ++++++++--------- doc/doxygen/headers/iterators.h | 15 +++++++-------- doc/doxygen/headers/lac.h | 15 +++++++-------- doc/doxygen/headers/laoperators.h | 15 +++++++-------- doc/doxygen/headers/main.h | 15 +++++++-------- doc/doxygen/headers/manifold.h | 17 ++++++++--------- doc/doxygen/headers/matrices.h | 17 ++++++++--------- doc/doxygen/headers/matrixfree.h | 15 +++++++-------- doc/doxygen/headers/memory.h | 15 +++++++-------- doc/doxygen/headers/mesh_worker.h | 15 +++++++-------- doc/doxygen/headers/mg.h | 15 +++++++-------- doc/doxygen/headers/multithreading.h | 15 +++++++-------- doc/doxygen/headers/namespace_dealii.h | 15 +++++++-------- doc/doxygen/headers/numerical_algorithms.h | 15 +++++++-------- doc/doxygen/headers/parallel.h | 17 ++++++++--------- doc/doxygen/headers/petsc.h | 17 ++++++++--------- doc/doxygen/headers/physics.h | 15 +++++++-------- doc/doxygen/headers/polynomials.h | 17 ++++++++--------- doc/doxygen/headers/preconditioners.h | 17 ++++++++--------- doc/doxygen/headers/quadrature.h | 15 +++++++-------- doc/doxygen/headers/reordering.h | 15 +++++++-------- doc/doxygen/headers/simplex.h | 15 +++++++-------- doc/doxygen/headers/slepc.h | 15 +++++++-------- doc/doxygen/headers/solvers.h | 17 ++++++++--------- doc/doxygen/headers/sparsity.h | 17 ++++++++--------- doc/doxygen/headers/trilinos.h | 15 +++++++-------- doc/doxygen/headers/update_flags.h | 17 ++++++++--------- doc/doxygen/headers/utilities.h | 15 +++++++-------- doc/doxygen/headers/vector_memory.h | 17 ++++++++--------- doc/doxygen/headers/vector_valued.h | 15 +++++++-------- doc/doxygen/headers/vectors.h | 15 +++++++-------- doc/doxygen/scripts/code-gallery.pl | 15 +++++++-------- doc/doxygen/scripts/create_anchors.pl | 15 +++++++-------- doc/doxygen/scripts/filter.pl | 15 +++++++-------- doc/doxygen/scripts/intro2toc.pl | 15 +++++++-------- doc/doxygen/scripts/make_gallery.pl | 15 +++++++-------- doc/doxygen/scripts/make_step.pl | 15 +++++++-------- doc/doxygen/scripts/mod_header.pl.in | 17 ++++++++--------- doc/doxygen/scripts/program2doxygen.pl | 15 +++++++-------- doc/doxygen/scripts/program2html.pl | 15 +++++++-------- doc/doxygen/scripts/program2plain.pl | 15 +++++++-------- doc/doxygen/scripts/program2toc.pl | 15 +++++++-------- doc/doxygen/scripts/set_canonical_doxygen.pl | 15 +++++++-------- doc/doxygen/scripts/steps.pl | 17 ++++++++--------- doc/doxygen/scripts/validate-xrefs.pl | 15 +++++++-------- doc/doxygen/tutorial/CMakeLists.txt | 14 ++++++-------- doc/doxygen/tutorial/tutorial.h.in | 17 ++++++++--------- doc/external-libs/p4est-setup.sh | 2 ++ doc/news/1.0.0-vs-2.0.0.h | 17 ++++++++--------- doc/news/2.0.0-vs-3.0.0.h | 17 ++++++++--------- doc/news/3.0.0-vs-3.0.1.h | 17 ++++++++--------- doc/news/3.0.0-vs-3.1.0.h | 17 ++++++++--------- doc/news/3.1.0-vs-3.1.1.h | 17 ++++++++--------- doc/news/3.1.0-vs-3.2.0.h | 17 ++++++++--------- doc/news/3.1.1-vs-3.1.2.h | 17 ++++++++--------- doc/news/3.2.0-vs-3.2.1.h | 17 ++++++++--------- doc/news/3.2.0-vs-3.3.0.h | 17 ++++++++--------- doc/news/3.3.0-vs-3.3.1.h | 17 ++++++++--------- doc/news/3.3.0-vs-3.4.0.h | 17 ++++++++--------- doc/news/3.4.0-vs-4.0.0.h | 17 ++++++++--------- doc/news/4.0.0-vs-5.0.0.h | 17 ++++++++--------- doc/news/5.0.0-vs-5.1.0.h | 17 ++++++++--------- doc/news/5.1.0-vs-5.2.0.h | 17 ++++++++--------- doc/news/5.2.0-vs-6.0.0.h | 17 ++++++++--------- doc/news/6.0.0-vs-6.1.0.h | 17 ++++++++--------- doc/news/6.1.0-vs-6.2.0.h | 17 ++++++++--------- doc/news/6.2.0-vs-6.2.1.h | 17 ++++++++--------- doc/news/6.2.0-vs-6.3.0.h | 17 ++++++++--------- doc/news/6.3.0-vs-6.3.1.h | 17 ++++++++--------- doc/news/6.3.0-vs-7.0.0.h | 17 ++++++++--------- doc/news/7.0.0-vs-7.1.0.h | 17 ++++++++--------- doc/news/7.1.0-vs-7.2.0.h | 17 ++++++++--------- doc/news/7.2.0-vs-7.3.0.h | 17 ++++++++--------- doc/news/7.3.0-vs-8.0.0.h | 17 ++++++++--------- doc/news/8.0.0-vs-8.1.0.h | 17 ++++++++--------- doc/news/8.1.0-vs-8.2.0.h | 17 ++++++++--------- doc/news/8.2.0-vs-8.2.1.h | 17 ++++++++--------- doc/news/8.2.1-vs-8.3.0.h | 17 ++++++++--------- doc/news/8.3.0-vs-8.4.0.h | 17 ++++++++--------- doc/news/8.4.0-vs-8.4.1.h | 17 ++++++++--------- doc/news/8.4.1-vs-8.4.2.h | 17 ++++++++--------- doc/news/8.4.2-vs-8.5.0.h | 17 ++++++++--------- doc/news/8.5.0-vs-9.0.0.h | 17 ++++++++--------- doc/news/9.0.0-vs-9.0.1.h | 17 ++++++++--------- doc/news/9.0.1-vs-9.1.0.h | 17 ++++++++--------- doc/news/9.1.0-vs-9.1.1.h | 17 ++++++++--------- doc/news/9.1.1-vs-9.2.0.h | 17 ++++++++--------- doc/news/9.2.0-vs-9.3.0.h | 17 ++++++++--------- doc/news/9.3.0-vs-9.3.1.h | 17 ++++++++--------- doc/news/9.3.1-vs-9.3.2.h | 17 ++++++++--------- doc/news/9.3.2-vs-9.3.3.h | 17 ++++++++--------- doc/news/9.3.3-vs-9.4.0.h | 17 ++++++++--------- doc/news/9.4.0-vs-9.5.0.h | 17 ++++++++--------- doc/news/9.5.0-vs-9.5.2.h | 17 ++++++++--------- doc/news/CMakeLists.txt | 14 ++++++-------- doc/news/changes/create_changes_h.cmake | 14 ++++++-------- doc/news/changes/header | 18 +++++++++--------- 124 files changed, 929 insertions(+), 1054 deletions(-) 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: 
-// ---------------------------------------------------------------------
+// ------------------------------------------------------------------------
 //
-// 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 "