diff --git a/MathFunctions.c b/MathFunctions.c
index 04a0969..5b52617 100644
--- a/MathFunctions.c
+++ b/MathFunctions.c
@@ -5,6 +5,8 @@
 // Level 00 Revision 01.16
 // October 30, 2014
 
+#include <string.h>
+
 #include "OsslCryptoEngine.h"
 //
 //