[1] REXMLのDoS脆弱性 ( 版) <http://www.ruby-lang.org/ja/news/2008/08/23/dos-vulnerability-in-rexml/>
[2] The Web Application Security Consortium / XML Entity Expansion ( 版) <http://projects.webappsec.org/w/page/13247002/XML%20Entity%20Expansion>
[3] RFC 3023 - XML Media Types ( 版) <http://tools.ietf.org/html/rfc3023#page-27>
[4] Billion laughs - Wikipedia, the free encyclopedia ( 版) <http://en.wikipedia.org/wiki/Billion_laughs>
[6] RFC 4918 - HTTP Extensions for Web Distributed Authoring and Versioning (WebDAV) ( 版) <http://tools.ietf.org/html/rfc4918#section-20.6>
[5] RFC 7303 - XML Media Types ( ( 版)) <http://tools.ietf.org/html/rfc7303#page-26>