diff --git a/ndn-cpp/util/changed-event.cpp b/ndn-cpp/util/changed-event.cpp
index 63b4569..08dcb98 100644
--- a/ndn-cpp/util/changed-event.cpp
+++ b/ndn-cpp/util/changed-event.cpp
@@ -1,3 +1,4 @@
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil -*- */
 /**
  * Copyright (C) 2013 Regents of the University of California.
  * @author: Jeff Thompson <jefft0@remap.ucla.edu>