%% You should probably cite draft-jesske-sipcore-sip-tree-cap-indicators instead of this I-D.
@techreport{allen-sipcore-sip-tree-cap-indicators-01,
    number =    {draft-allen-sipcore-sip-tree-cap-indicators-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-allen-sipcore-sip-tree-cap-indicators/01/},
    author =    {Andrew Allen},
    title =     {{Internet Assigned Numbers Authority (IANA) Registration of the Session Initiation Protocol (SIP) Feature-Capability indicators}},
    pagetotal = 21,
    year =      2014,
    month =     jul,
    day =       4,
    abstract =  {This document registers with IANA the SIP Feature-Capability indicators in the "SIP Feature-Capability Indicator Registration Tree" of the IANA "Proxy-Feature Feature-Capability Indicator Trees" registry for use with the SIP Feature-Caps header field.},
}