diff --git a/CMakeLists.txt b/CMakeLists.txt
index b6e8daa..8414a0e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -64,7 +64,10 @@ if (UNIT_TESTING)
         message(STATUS "Found CppUTest version ${CPPUTEST_VERSION}")
     endif()
     
-    include_directories(${CPPUTEST_INCLUDE_DIRS} ../src/)
+    include_directories(
+        ${CPPUTEST_INCLUDE_DIRS}
+        /usr/include/c++/11/
+        )
     link_directories(${CPPUTEST_LIBRARIES})
 
     message(STATUS "CPPUTEST_DIR: ${CPPUTEST_DIR}")