diff --git a/tools/ping/ndn-ping-server.cpp b/tools/ping/ndn-ping-server.cpp
index 684891c..d508e6c 100644
--- a/tools/ping/ndn-ping-server.cpp
+++ b/tools/ping/ndn-ping-server.cpp
@@ -1,4 +1,21 @@
-/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil -*- */
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2014-2015,  Arizona Board of Regents.
+ *
+ * This file is part of ndn-tools (Named Data Networking Essential Tools).
+ * See AUTHORS.md for complete list of ndn-tools authors and contributors.
+ *
+ * ndn-tools is free software: you can redistribute it and/or modify it under the terms
+ * of the GNU General Public License as published by the Free Software Foundation,
+ * either version 3 of the License, or (at your option) any later version.
+ *
+ * ndn-tools is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+ * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
+ * PURPOSE.  See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * ndn-tools, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
+ */
 /**
  * Copyright (C) 2014 Arizona Board of Regents
  *
diff --git a/tools/ping/ndn-ping.cpp b/tools/ping/ndn-ping.cpp
index 4abfcec..11591a6 100644
--- a/tools/ping/ndn-ping.cpp
+++ b/tools/ping/ndn-ping.cpp
@@ -1,4 +1,21 @@
-/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil -*- */
+/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
+/**
+ * Copyright (c) 2014-2015,  Arizona Board of Regents.
+ *
+ * This file is part of ndn-tools (Named Data Networking Essential Tools).
+ * See AUTHORS.md for complete list of ndn-tools authors and contributors.
+ *
+ * ndn-tools is free software: you can redistribute it and/or modify it under the terms
+ * of the GNU General Public License as published by the Free Software Foundation,
+ * either version 3 of the License, or (at your option) any later version.
+ *
+ * ndn-tools is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+ * without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
+ * PURPOSE.  See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * ndn-tools, e.g., in COPYING.md file.  If not, see <http://www.gnu.org/licenses/>.
+ */
 /**
  * Copyright (C) 2014 Arizona Board of Regents
  *