[1] RFC 2026 - The Internet Standards Process -- Revision 3 (2017-01-29 17:15:51 +09:00) <https://tools.ietf.org/html/rfc2026>

[2] RFC Errata Report » RFC Editor (2017-02-09 18:13:56 +09:00) <https://www.rfc-editor.org/errata_search.php?rfc=2026>