[1] [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>

[2] [CITE@en[RFC 5545 - Internet Calendaring and Scheduling Core Object Specification (iCalendar)]]
( ([TIME[2016-06-19 16:13:42 +09:00]]))
<https://tools.ietf.org/html/rfc5545#section-3.6.5>

[3] [CITE@en[RFC 4791 - Calendaring Extensions to WebDAV (CalDAV)]]
([TIME[2017-09-24 16:22:36 +09:00]])
<https://tools.ietf.org/html/rfc4791#section-4.1>