Index: ng/CMakeLists.txt
--- ng/CMakeLists.txt.orig
+++ ng/CMakeLists.txt
@@ -37,7 +37,7 @@ endif(USE_GUI)
 if(USE_PYTHON)
     add_library(ngpy SHARED netgenpy.cpp)
     target_link_libraries( ngpy PUBLIC nglib PRIVATE "$<BUILD_INTERFACE:netgen_python>" )
-    target_link_libraries( ngpy PRIVATE ${CMAKE_THREAD_LIBS_INIT} ${JPEG_LIBRARIES} ${MKL_LIBRARIES} ${ZLIB_LIBRARIES} occ_libs netgen_cgns )
+    target_link_libraries( ngpy PRIVATE ${CMAKE_THREAD_LIBS_INIT} ${JPEG_LIBRARIES} ${MKL_LIBRARIES} ${ZLIB_LIBRARIES} occ_libs netgen_cgns -L/usr/X11R6/lib)
     if(APPLE)
         set_target_properties( ngpy PROPERTIES SUFFIX ".so")
     elseif(WIN32)
