diff --git a/BGL/include/CGAL/boost/graph/IO/PLY.h b/BGL/include/CGAL/boost/graph/IO/PLY.h
index d4986001cd1..20883ffdfd3 100644
--- a/BGL/include/CGAL/boost/graph/IO/PLY.h
+++ b/BGL/include/CGAL/boost/graph/IO/PLY.h
@@ -388,7 +388,7 @@ bool write_PLY(std::ostream& os,
   {
     auto vnm = get_parameter(np, internal_np::vertex_normal_map);
     typedef decltype(vnm) Normal_map;
-    typedef Kernel_traits<typename Normal_map::value_type>::Kernel::FT FloatDouble;
+    typedef typename Kernel_traits<typename Normal_map::value_type>::Kernel::FT FloatDouble;
     if(std::is_same<FloatDouble, float>::value)
       {
         os << "property float nx" << std::endl