diff --git a/Weights/include/CGAL/Weights/cotangent_weights.h b/Weights/include/CGAL/Weights/cotangent_weights.h
index ce3471550b5..ba128a98502 100644
--- a/Weights/include/CGAL/Weights/cotangent_weights.h
+++ b/Weights/include/CGAL/Weights/cotangent_weights.h
@@ -209,7 +209,7 @@ private:
   // is used, but Surface_mesh_deformation has its own weight API locked
   // by the concept SurfaceMeshDeformationWeights.
   // A bit awkward, but better than duplicating code...
-  PolygonMesh* const* m_pmesh_ptr;
+  PolygonMesh const * const m_pmesh_ptr;
   const VertexPointMap m_vpm;
   const GeomTraits m_traits;