%% You should probably cite rfc4508 instead of this I-D.
@techreport{ietf-sip-refer-feature-param-01,
    number =    {draft-ietf-sip-refer-feature-param-01},
    type =      {Internet-Draft},
    institution =   {Internet Engineering Task Force},
    publisher = {Internet Engineering Task Force},
    note =      {Work in Progress},
    url =       {https://datatracker.ietf.org/doc/draft-ietf-sip-refer-feature-param/01/},
    author =    {Alan Johnston and Orit Levin},
    title =     {{Conveying Feature Tags with the Session Initiation Protocol (SIP) REFER Method}},
    pagetotal = 6,
    year =      2006,
    month =     jan,
    day =       17,
    abstract =  {The SIP "Caller Preferences" extension defined in RFC 3840 provides a mechanism that allows a SIP request to convey information relating to the originator's capabilities and preferences for handling of that request. The SIP REFER method defined in RFC 3515 provides a mechanism that allows one party to induce another to initiate a SIP request. This document extends the REFER method to use the mechanism of RFC 3840. By doing so, the originator of a REFER may inform the recipient as to the characteristics of the target that the induced request is expected to reach. {[}STANDARDS-TRACK{]}},
}