[1]
[CITE@en[RFC 4791 - Calendaring Extensions to WebDAV (CalDAV)]] ([TIME[2017-09-24 16:22:36 +09:00]]) <https://tools.ietf.org/html/rfc4791>

[2] [CITE@en[RFC 6638 - Scheduling Extensions to CalDAV]]
( ([TIME[2012-07-24 11:19:02 +09:00]] 版))
<http://tools.ietf.org/html/rfc6638>

[3] [CITE@en[RFC 7809 - Calendaring Extensions to WebDAV (CalDAV): Time Zones by Reference]]
([TIME[2016-04-02 09:16:11 +09:00]] 版)
<https://tools.ietf.org/html/rfc7809>

[4] [CITE[RFC Errata Report » RFC Editor]]
([TIME[2017-10-01 21:26:57 +09:00]])
<https://www.rfc-editor.org/errata_search.php?rfc=4791>