diff -r cd72eae05bdf -r 3c00344f49c9 doc/Doxyfile.in
--- a/doc/Doxyfile.in	Mon Jul 16 16:21:40 2018 +0200
+++ b/doc/Doxyfile.in	Wed Oct 17 19:14:07 2018 +0200
@@ -77,6 +77,7 @@
 SHOW_NAMESPACES        = YES
 FILE_VERSION_FILTER    = 
 LAYOUT_FILE            = "@abs_top_srcdir@/doc/DoxygenLayout.xml"
+CITE_BIB_FILES         = "@abs_top_srcdir@/doc/references.bib"
 #---------------------------------------------------------------------------
 # configuration options related to warning and progress messages
 #---------------------------------------------------------------------------
@@ -95,10 +96,10 @@
                          "@abs_top_srcdir@/lemon/bits" \
                          "@abs_top_srcdir@/lemon/concepts" \
                          "@abs_top_srcdir@/demo" \
+                         "@abs_top_srcdir@/contrib" \
                          "@abs_top_srcdir@/tools" \
                          "@abs_top_srcdir@/test/test_tools.h" \
-                         "@abs_top_builddir@/doc/mainpage.dox" \
-                         "@abs_top_builddir@/doc/references.dox"
+                         "@abs_top_builddir@/doc/mainpage.dox"
 INPUT_ENCODING         = UTF-8
 FILE_PATTERNS          = *.h \
                          *.cc \
@@ -181,8 +182,8 @@
 EXT_LINKS_IN_WINDOW    = NO
 FORMULA_FONTSIZE       = 10
 FORMULA_TRANSPARENT    = YES
-USE_MATHJAX            = NO
-MATHJAX_RELPATH        = http://www.mathjax.org/mathjax
+USE_MATHJAX            = @LEMON_DOC_USE_MATHJAX@
+MATHJAX_RELPATH        = @LEMON_DOC_MATHJAX_RELPATH@
 SEARCHENGINE           = YES
 SERVER_BASED_SEARCH    = NO
 #---------------------------------------------------------------------------
@@ -252,7 +253,7 @@
 #---------------------------------------------------------------------------
 # Configuration::additions related to external references
 #---------------------------------------------------------------------------
-TAGFILES               = "@abs_top_builddir@/doc/libstdc++.tag = http://gcc.gnu.org/onlinedocs/libstdc++/latest-doxygen/  "
+TAGFILES               = "@abs_top_builddir@/doc/libstdc++.tag = @LEMON_DOC_LIBSTDC++_URL@"
 GENERATE_TAGFILE       = html/lemon.tag
 ALLEXTERNALS           = NO
 EXTERNAL_GROUPS        = NO