docs: License statement correction

Change-Id: Id57c519f7b4b298d36736a23f0b41a7303a7b960
Refs: #1885
diff --git a/README.md b/README.md
index 1847c3c..365736a 100644
--- a/README.md
+++ b/README.md
@@ -27,4 +27,4 @@
 ## License
 
 ndn-cxx is an open source project licensed under LGPL 3.0 license. For more information about
-the license, refer to [`COPYING`](https://github.com/named-data/ndn-cxx/blob/master/COPYING).
+the license, refer to [`COPYING.md`](https://github.com/named-data/ndn-cxx/blob/master/COPYING.md).