diff --git a/doc/Doxyfile.extra.in b/doc/Doxyfile.extra.in
index 6ccbca2b6c6f0082f6d598e1cbb7ac0b089a48c6..67cb6e6ae961e711f4d062355d0714e934e244f5 100644
--- a/doc/Doxyfile.extra.in
+++ b/doc/Doxyfile.extra.in
@@ -1,5 +1,6 @@
 INPUT                  = @CMAKE_SOURCE_DIR@/include \
-		         @CMAKE_SOURCE_DIR@/doc/additionalHeader
+		         @CMAKE_SOURCE_DIR@/doc/additionalHeader \
+			 @CMAKE_SOURCE_DIR@/src
 IMAGE_PATH             = @CMAKE_SOURCE_DIR@/doc/pictures
 
 TAGFILES               = \