%% You should probably cite draft-vanelburg-dispatch-private-network-ind instead of this I-D.
@techreport{vanelburg-sipping-private-network-indication-03,
    number =    {draft-vanelburg-sipping-private-network-indication-03},
    type =      {Internet-Draft},
    institution =   {Internet Engineering Task Force},
    publisher = {Internet Engineering Task Force},
    note =      {Work in Progress},
    url =       {https://datatracker.ietf.org/doc/draft-vanelburg-sipping-private-network-indication/03/},
    author =    {Keith Drage and Hans Erik van Elburg},
    title =     {{The Session Initiation Protocol (SIP) P-Private-Network-Indication Private-Header (P-Header)}},
    pagetotal = 18,
    year =      2009,
    month =     feb,
    day =       19,
    abstract =  {This document describes why a private network indication is needed. A private network indication allows other nodes in a network to treat private network traffic to a different set of rules then public network traffic. The indication also distinguishes one private network from another private network.},
}