%% You should probably cite rfc8443 instead of this I-D.
@techreport{ietf-stir-rph-06,
    number =    {draft-ietf-stir-rph-06},
    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/06/},
    author =    {Ray P. Singh and Martin Dolly and Subir Das and An Nguyen},
    title =     {{Personal Assertion Token (PASSporT) Extension for Resource Priority Authorization}},
    pagetotal = 10,
    year =      2018,
    month =     may,
    day =       24,
    abstract =  {This document extends the Personal Assertion Token (PASSporT) specification defined in RFC 8225 to allow the inclusion of cryptographically signed assertions of authorization for the values populated in the Session Initiation Protocol (SIP) 'Resource-Priority' header field, which is used for communications resource prioritization.},
}