Non-Gregorian Recurrence Rules in the Internet Calendaring and Scheduling Core Object Specification (iCalendar)

Non-Gregorian Recurrence Rules in the Internet Calendaring and Scheduling Core Object Specification (iCalendar) Apple Inc. Google Inc. This document defines extensions to the Internet Calendaring and Scheduling Core Object Specification (iCalendar) (RFC 5545) to support use of non-Gregorian recurrence rules. It also defines how Calendaring Extensions to WebDAV (CalDAV) (RFC 4791) servers and clients can be extended to support these new recurrence rules.