%% You should probably cite rfc8443 instead of this I-D.
@techreport{ietf-stir-rph-02,
    number =    {draft-ietf-stir-rph-02},
    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-stir-rph/02/},
    author =    {Ray P. Singh and Martin Dolly and Subir Das and An Nguyen},
    title =     {{PASSporT Extension for Resource-Priority Authorization}},
    pagetotal = 9,
    year =      2018,
    month =     jan,
    day =       4,
    abstract =  {This document extends the STIR PASSporT specification to allow the inclusion of cryptographically-signed assertions of authorization for the values populated in the SIP 'Resource-Priority' header field, which is used for communications resource prioritization.},
}