diff --git a/Segment_Delaunay_graph_Linf_2/include/CGAL/Segment_Delaunay_graph_Linf_2/Voronoi_vertex_sqrt_field_new_C2.h b/Segment_Delaunay_graph_Linf_2/include/CGAL/Segment_Delaunay_graph_Linf_2/Voronoi_vertex_sqrt_field_new_C2.h
index 41d9e22fdd4..5c0e63916ef 100644
--- a/Segment_Delaunay_graph_Linf_2/include/CGAL/Segment_Delaunay_graph_Linf_2/Voronoi_vertex_sqrt_field_new_C2.h
+++ b/Segment_Delaunay_graph_Linf_2/include/CGAL/Segment_Delaunay_graph_Linf_2/Voronoi_vertex_sqrt_field_new_C2.h
@@ -26,7 +26,7 @@
 #include <CGAL/license/Segment_Delaunay_graph_Linf_2.h>
 
 
-
+#include <fstream>
 
 #include <CGAL/Segment_Delaunay_graph_Linf_2/Basic_predicates_C2.h>
 #include <CGAL/Segment_Delaunay_graph_2/Are_same_points_C2.h>