%% You should probably cite rfc4415 instead of this I-D.
@techreport{ietf-enum-voice-01,
    number =    {draft-ietf-enum-voice-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-voice/01/},
    author =    {Lawrence W. Conroy and Rudolf Brandner and Richard Stastny},
    title =     {{IANA Registration for Enumservice Voice}},
    pagetotal = 8,
    year =      2005,
    month =     oct,
    day =       21,
    abstract =  {This document registers the Enumservice "voice" (which has a defined subtype "tel"), as per the IANA registration process defined in the ENUM specification RFC 3761. This service indicates that the contact held in the generated Uniform Resource Identifier (URI) can be used to initiate an interactive voice (audio) call. {[}STANDARDS-TRACK{]}},
}