[1] draft-girod-w3-id-res-ext-00 - WIRE - W3 Identifier Resolution Extensions (2014-10-18 15:53:54 +09:00 版) <http://tools.ietf.org/html/draft-girod-w3-id-res-ext-00#section-2.2.1>

[2] RFC 4229 - HTTP Header Field Registrations (2014-11-02 18:53:20 +09:00 版) <http://tools.ietf.org/html/rfc4229#section-2.2.6>