%% You should probably cite rfc4349 instead of this I-D.
@techreport{ietf-l2tpext-pwe3-hdlc-07,
    number =    {draft-ietf-l2tpext-pwe3-hdlc-07},
    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-l2tpext-pwe3-hdlc/07/},
    author =    {Carlos Pignataro and Mark Townsley},
    title =     {{High-Level Data Link Control (HDLC) Frames over Layer 2 Tunneling Protocol, Version 3 (L2TPv3)}},
    pagetotal = 11,
    year =      2005,
    month =     sep,
    day =       9,
    abstract =  {The Layer 2 Tunneling Protocol, Version 3, (L2TPv3) defines a protocol for tunneling a variety of data link protocols over IP networks. This document describes the specifics of how to tunnel High-Level Data Link Control (HDLC) frames over L2TPv3. {[}STANDARDS-TRACK{]}},
}