diff --git a/docs/doxygen.conf.in b/docs/doxygen.conf.in
index 8cb8bcb..e353524 100644
--- a/docs/doxygen.conf.in
+++ b/docs/doxygen.conf.in
@@ -2031,7 +2031,7 @@
 # preprocessor.
 # This tag requires that the tag SEARCH_INCLUDES is set to YES.
 
-INCLUDE_PATH           =
+INCLUDE_PATH           = ..
 
 # 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