[1] RFC 4791 - Calendaring Extensions to WebDAV (CalDAV) () <https://tools.ietf.org/html/rfc4791>
[2] RFC 6638 - Scheduling Extensions to CalDAV ( ( 版)) <http://tools.ietf.org/html/rfc6638>
[3] RFC 7809 - Calendaring Extensions to WebDAV (CalDAV): Time Zones by Reference ( 版) <https://tools.ietf.org/html/rfc7809>
[4] RFC Errata Report » RFC Editor () <https://www.rfc-editor.org/errata_search.php?rfc=4791>