RFC 2425 - A MIME Content-Type for Directory Infor
Defines a MIME Content-Type for holding directory information. The definition is independent of any particular directory service or protocol. The text/directory Content-Type is defined for holding a variety of directory information, for example, name, or email address, or logo.
RFC 2426 - vCard MIME Directory Profile
Defines the profile of the MIME Content-Type for directory information for a white-pages person object, based on a vCard electronic business card. The profile is defined for representing and exchanging a variety of information about an individual.
vCard Overview
Discuess features and applications of vCard. (Internet Mail Consortium)
vCard: The Electronic Business Card
A whitepaper on vCard, the personal data interchange standard. (Internet Mail Consortium)