diff --git a/Doc/Doxygen/core/Doxyfile.in b/Doc/Doxygen/core/Doxyfile.in
index 1b2db7d2a29cec9fcfe0e4500d7d1c725f941261..070fb3f9209eb90421c0f4a85328b412c03891c7 100644
--- a/Doc/Doxygen/core/Doxyfile.in
+++ b/Doc/Doxygen/core/Doxyfile.in
@@ -969,7 +969,7 @@ EXCLUDE_SYMLINKS       = NO
 # Note that the wildcards are matched against the file with absolute path, so to
 # exclude all test directories for example use the pattern */test/*
 
-EXCLUDE_PATTERNS       = */3rdParty/* \
+EXCLUDE_PATTERNS       = */3rdparty/* \
                          */Test/*
 
 # The EXCLUDE_SYMBOLS tag can be used to specify one or more symbol names