diff --git a/doc/reference/Doxyfile.in b/doc/reference/Doxyfile.in
index 76fc226..8ab6642 100644
--- a/doc/reference/Doxyfile.in
+++ b/doc/reference/Doxyfile.in
@@ -191,8 +191,6 @@ REFERENCES_LINK_SOURCE = YES
 SOURCE_TOOLTIPS        = YES
 USE_HTAGS              = NO
 VERBATIM_HEADERS       = YES
-CLANG_ASSISTED_PARSING = NO
-CLANG_OPTIONS          = 
 
 # ==============================================================================
 # Options related to alphabetical class index