[1] draft-murchison-webdav-prefer-07 - Use of the Prefer Header Field in Web Distributed Authoring and Versioning (WebDAV) ( ( 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) () <https://tools.ietf.org/html/rfc8144>