http://stackoverflow.com/questions/671118/what-exactly-is-restful-programming
http://stackoverflow.com/questions/671118/what-exactly-is-restful-programming
http://www.ibm.com/developerworks/webservices/library/ws-restful/
Tac gia cua REST la
https://www.ics.uci.edu/~fielding/pubs/dissertation/top.htm