diff --git a/include/Nazara/Math/Plane.inl b/include/Nazara/Math/Plane.inl
index dbe80f1fd..dd7d5f108 100644
--- a/include/Nazara/Math/Plane.inl
+++ b/include/Nazara/Math/Plane.inl
@@ -3,6 +3,7 @@
 // For conditions of distribution and use, see copyright notice in Config.hpp
 
 #include <Nazara/Core/Algorithm.hpp>
+#include <Nazara/Core/StringExt.hpp>
 #include <cstring>
 #include <sstream>
 #include <Nazara/Core/Debug.hpp>