diff --git a/doc/Doxyfile.in b/doc/Doxyfile.in
index 9b81c1af2..e8e7261b8 100644
--- a/doc/Doxyfile.in
+++ b/doc/Doxyfile.in
@@ -1998,7 +1998,7 @@ SEARCH_INCLUDES        = YES
 # preprocessor.
 # This tag requires that the tag SEARCH_INCLUDES is set to YES.
 
-INCLUDE_PATH           =
+INCLUDE_PATH           = @abs_top_srcdir@/include
 
 # You can use the INCLUDE_FILE_PATTERNS tag to specify one or more wildcard
 # patterns (like *.h and *.hpp) to filter out the header-files in the