Identify the calendar addresses of the associated principal resource. Protected: This property MAY be protected.
PROPFIND behavior: This property SHOULD NOT be returned by a PROPFIND DAV:allprop request (as defined in Section 14.2 of [RFC4918]).
COPY/MOVE behavior: This property value SHOULD be preserved in COPY and MOVE operations.
Support for this property is REQUIRED. This property is needed to map calendar user addresses in iCalendar data to principal resources and their associated scheduling Inbox and Outbox collections. In the event that a user has no well-defined identifier for his calendar user address, the URI of his principal resource can be used. This property SHOULD be searchable using the DAV:principal-property-search REPORT. The DAV:principal- search-property-set REPORT SHOULD identify this property as such. If not present, then the associated calendar user is not enabled for scheduling on the server.