Merge with master

diff --cc doc/doxygen/references.bib
Simple merge

diff --cc include/deal.II/lac/petsc_precondition.h
index a4fa95a2ec794d594ffaabe19e086e29dfcbda54,e4bf24814f64a4f27647507b6c60c3f306fdac97..5304d0b0ec505ede9183ab2a1d5c979bf46e49c0
--- 1/include/deal.II/lac/petsc_precondition.h
--- 2/include/deal.II/lac/petsc_precondition.h
+++ b/include/deal.II/lac/petsc_precondition.h
@@@ -14,19 -14,18 +14,19 @@@
  // ---------------------------------------------------------------------
  
  #ifndef dealii_petsc_precondition_h
- #  define dealii_petsc_precondition_h
+ #define dealii_petsc_precondition_h
  
  
- #  include <deal.II/base/config.h>
+ #include <deal.II/base/config.h>
  
- #  include <deal.II/base/point.h>
- #  include <deal.II/base/subscriptor.h>
++#include <deal.II/base/point.h>
+ #include <deal.II/base/subscriptor.h>
  
- #  ifdef DEAL_II_WITH_PETSC
+ #ifdef DEAL_II_WITH_PETSC
  
- #    include <deal.II/lac/exceptions.h>
+ #  include <deal.II/lac/exceptions.h>
  
- #    include <petscpc.h>
+ #  include <petscpc.h>
  
  DEAL_II_NAMESPACE_OPEN
  

diff --cc include/deal.II/lac/petsc_sparse_matrix.h
index 473eaf4bf2b70bf447c3d8e9185d23d963ac4b53,d4640f4a752e920eeeef85d9af6115ccc311dfa3..08d7734571adcf133f393b75d1095e15800d9d83
--- 1/include/deal.II/lac/petsc_sparse_matrix.h
--- 2/include/deal.II/lac/petsc_sparse_matrix.h
+++ b/include/deal.II/lac/petsc_sparse_matrix.h
@@@ -14,21 -14,18 +14,21 @@@
  // ---------------------------------------------------------------------
  
  #ifndef dealii_petsc_sparse_matrix_h
- #  define dealii_petsc_sparse_matrix_h
+ #define dealii_petsc_sparse_matrix_h
  
  
- #  include <deal.II/base/config.h>
+ #include <deal.II/base/config.h>
  
- #  ifdef DEAL_II_WITH_PETSC
+ #ifdef DEAL_II_WITH_PETSC
  
- #    include <deal.II/lac/exceptions.h>
- #    include <deal.II/lac/petsc_matrix_base.h>
- #    include <deal.II/lac/petsc_vector.h>
+ #  include <deal.II/lac/exceptions.h>
+ #  include <deal.II/lac/petsc_matrix_base.h>
+ #  include <deal.II/lac/petsc_vector.h>
  
- #    include <petscis.h>
- #    include <petscistypes.h>
++#  include <petscis.h>
++#  include <petscistypes.h>
 +
- #    include <vector>
+ #  include <vector>
  
  DEAL_II_NAMESPACE_OPEN
  // forward declaration

diff --cc source/lac/petsc_parallel_sparse_matrix.cc
Simple merge