diff --git a/simgear/scene/sky/cloudfield.hxx b/simgear/scene/sky/cloudfield.hxx
index 0d8fba52..d962ae4f 100644
--- a/simgear/scene/sky/cloudfield.hxx
+++ b/simgear/scene/sky/cloudfield.hxx
@@ -44,7 +44,7 @@ namespace osg
 
 #include <simgear/misc/sg_path.hxx>
 #include <simgear/structure/Singleton.hxx>
-#include <Simgear/math/SGMath.hxx>
+#include <simgear/math/SGMath.hxx>
 
 using std::vector;