In vCard 4.0 specification each property has cardinality specified in RFC 6350
How do I find out cardinality for vCard 2.1 and 3.0? Are there any sign what the property with the same name can be included more than once in vCard 2.1 and 3.0?
From the official mailing list:
On 2012-05-14 10:13, Andrew Pace wrote:
Is there a list of properties with cardinality for Vcard3.0, like it is shown in RFC6350?
No, it does not exist. That's one of the many "bugs" in vCard 3.0 that were fixed in 4.0.
Simon
Reference: http://comments.gmane.org/gmane.ietf.vcarddav/313