diff --git a/tz.cpp b/tz.cpp
index cdd860e..34c2e73 100644
--- a/tz.cpp
+++ b/tz.cpp
@@ -1,6 +1,7 @@
 // The MIT License (MIT)
 // 
 // Copyright (c) 2015 Howard Hinnant
+// Copyright (c) 2015 Ville Voutilainen
 // 
 // Permission is hereby granted, free of charge, to any person obtaining a copy
 // of this software and associated documentation files (the "Software"), to deal