diff --git a/Point_set_processing_3/include/CGAL/vcm_estimate_normals.h b/Point_set_processing_3/include/CGAL/vcm_estimate_normals.h
index 492d45108b6..d377343f974 100644
--- a/Point_set_processing_3/include/CGAL/vcm_estimate_normals.h
+++ b/Point_set_processing_3/include/CGAL/vcm_estimate_normals.h
@@ -28,6 +28,7 @@
 #include <CGAL/Point_set_processing_3/internal/Voronoi_covariance_3/voronoi_covariance_3.h>
 
 #include <CGAL/property_map.h>
+#include <CGAL/point_set_processing_assertions.h>
 #include <CGAL/Delaunay_triangulation_3.h>
 #include <CGAL/Kd_tree.h>
 #include <CGAL/Search_traits_3.h>