[1] List of HTTP status codes - Wikipedia, the free encyclopedia ( (2012-02-19 13:30:55 +09:00 版)) http://en.wikipedia.org/wiki/List_of_HTTP_status_codes

[2] List of HTTP status codes - Wikipedia, the free encyclopedia ( (2013-10-01 11:44:11 +09:00 版)) http://en.wikipedia.org/wiki/List_of_HTTP_status_codes#499

[3]

HTTP/1.1 499 Client Disconnected
Connection: keep-alive
Server: Cowboy