diff --git a/README.md b/README.md
index 428fc497f..e5ddfab2c 100644
--- a/README.md
+++ b/README.md
@@ -84,7 +84,7 @@ non-exclusive right to your contributed code under MIT license.  If you want to
 be named as one of mruby developers, please include an update to the AUTHORS
 file in your pull request.
 
-[ISO-standard]: http://www.iso.org/iso/iso_catalogue/catalogue_tc/catalogue_detail.htm?csnumber=59579		
-[build-status-img]: https://travis-ci.org/mruby/mruby.svg?branch=master	
-[contribution-guidelines]: CONTRIBUTING.md		
+[ISO-standard]: http://www.iso.org/iso/iso_catalogue/catalogue_tc/catalogue_detail.htm?csnumber=59579
+[build-status-img]: https://travis-ci.org/mruby/mruby.svg?branch=master
+[contribution-guidelines]: CONTRIBUTING.md
 [travis-ci]: https://travis-ci.org/mruby/mruby