%% You should probably cite rfc4245 instead of this I-D.
@techreport{ietf-sipping-conferencing-requirements-01,
    number =    {draft-ietf-sipping-conferencing-requirements-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-sipping-conferencing-requirements/01/},
    author =    {Orit Levin and Roni Even},
    title =     {{High-Level Requirements for Tightly Coupled SIP Conferencing}},
    pagetotal = 12,
    year =      2004,
    month =     oct,
    day =       7,
    abstract =  {This document examines a wide range of conferencing requirements for tightly coupled SIP conferences. Separate documents will map the requirements to existing protocol primitives, define new protocol extensions, and introduce new protocols as needed. Together, these documents will provide a guide for building interoperable SIP conferencing applications. This memo provides information for the Internet community.},
}