[1] draft-murchison-webdav-prefer-07 - Use of the Prefer Header Field in Web Distributed Authoring and Versioning (WebDAV) ( (2014-10-16 14:20:11 +09:00 版)) http://tools.ietf.org/html/draft-murchison-webdav-prefer-07#section-4

[2] RFC 8144 - Use of the Prefer Header Field in Web Distributed Authoring and Versioning (WebDAV) (2017-04-19 23:22:44 +09:00) https://tools.ietf.org/html/rfc8144