[1] RFC 5537 - Netnews Architecture and Protocols (2009-12-29 07:15:42 +09:00 版) <http://tools.ietf.org/html/rfc5537>

[2] RFC Errata Report ( (2014-12-04 18:47:47 +09:00 版)) <http://www.rfc-editor.org/errata_search.php?rfc=5537>