diff --git a/include/Utilities/Checks.h b/include/Utilities/Checks.h
index b4c186d..eb684ea 100644
--- a/include/Utilities/Checks.h
+++ b/include/Utilities/Checks.h
@@ -2,6 +2,7 @@
 #define CHECKS_H_
 
 #include<algorithm>
+#include<string>
 #include<cstdlib>
 #include<ctype.h>