@misc{rfc6140,
    series =    {Request for Comments},
    number =    6140,
    howpublished =  {RFC 6140},
    publisher = {RFC Editor},
    doi =       {10.17487/RFC6140},
    url =       {https://www.rfc-editor.org/info/rfc6140},
    author =    {Adam Roach},
    title =     {{Registration for Multiple Phone Numbers in the Session Initiation Protocol (SIP)}},
    pagetotal = 35,
    year =      2011,
    month =     mar,
    abstract =  {This document defines a mechanism by which a Session Initiation Protocol (SIP) server acting as a traditional Private Branch Exchange (PBX) can register with a SIP Service Provider (SSP) to receive phone calls for SIP User Agents (UAs). In order to function properly, this mechanism requires that each of the Addresses of Record (AORs) registered in bulk map to a unique set of contacts. This requirement is satisfied by AORs representing phone numbers regardless of the domain, since phone numbers are fully qualified and globally unique. This document therefore focuses on this use case. {[}STANDARDS-TRACK{]}},
}