diff --git a/vcg/complex/algorithms/voronoi_processing.h b/vcg/complex/algorithms/voronoi_processing.h
index bfb1cc77..a5201a86 100644
--- a/vcg/complex/algorithms/voronoi_processing.h
+++ b/vcg/complex/algorithms/voronoi_processing.h
@@ -29,7 +29,7 @@
 #include<vcg/complex/algorithms/refine.h>
 #include<vcg/complex/algorithms/smooth.h>
 #include<vcg/space/fitting3.h>
-
+#include<wrap/callback.h>
 
 namespace vcg
 {