http://flag-icon-css.lip.is/

https://github.com/lipis/flag-icon-css

This project wouldn't exist without the awesome and now deleted collection of SVG flags by koppi.
https://github.com/koppi

Copyright (c) 2013 Panayiotis Lipiridis - The MIT License (MIT)
https://github.com/lipis/flag-icon-css/blob/master/LICENSE