diff --git a/vcg/math/histogram.h b/vcg/math/histogram.h
index 829106ab..4a3ddc26 100644
--- a/vcg/math/histogram.h
+++ b/vcg/math/histogram.h
@@ -26,6 +26,7 @@
 #include <assert.h>
 #include <string>
 #include <limits>
+#include <vector>
 #include <vcg/math/base.h>
 #include <stdio.h>