README.md in openbd_api-0.2.0 vs README.md in openbd_api-0.2.1

- old
+ new

@@ -1,10 +1,10 @@
 # OpenBD
 
 [![Gem Version](https://badge.fury.io/rb/openbd_api.svg)](https://badge.fury.io/rb/openbd_api)
 [![Build Status](https://travis-ci.org/nasum/openbd.svg?branch=master)](https://travis-ci.org/nasum/openbd)
 
-This gem wraps openBD Web API.
+This gem wraps [openBD](https://openbd.jp/) Web API.
 
 ## Installation
 
 Add this line to your application's Gemfile:
 