diff --git a/dtwc/fileOperations.hpp b/dtwc/fileOperations.hpp
index 2f7b1de..3380f23 100644
--- a/dtwc/fileOperations.hpp
+++ b/dtwc/fileOperations.hpp
@@ -21,6 +21,8 @@
 #include <utility>    // for pair
 #include <vector>     // for vector
 #include <fstream>
+#include <string>
+#include <sstream>
 
 namespace dtwc {