%% You should probably cite rfc3764 instead of this I-D.
@techreport{ietf-enum-sip-01,
    number =    {draft-ietf-enum-sip-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-enum-sip/01/},
    author =    {Jon Peterson},
    title =     {{enumservice registration for Session Initiation Protocol (SIP) Addresses-of-Record}},
    pagetotal = 8,
    year =      2003,
    month =     dec,
    day =       1,
    abstract =  {This document registers an Electronic Number (ENUM) service for the Session Initiation Protocol (SIP), pursuant to the guidelines in RFC 3761. Specifically, this document focuses on provisioning SIP addresses-of-record in ENUM. {[}STANDARDS-TRACK{]}},
}