%% You should probably cite rfc3301 instead of this I-D.
@techreport{ietf-l2tpext-atmext-04,
    number =    {draft-ietf-l2tpext-atmext-04},
    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-atmext/04/},
    author =    {Bernard Sales and Paolo Crivellari},
    title =     {{Layer Two Tunnelling Protocol (L2TP): ATM access network extensions}},
    pagetotal = 19,
    year =      2001,
    month =     feb,
    day =       23,
    abstract =  {L2TP {[}RFC2661{]} specifies a protocol for tunnelling PPP packets over packet based networks and over IP networks in particular. L2TP {[}RFC2661{]} supports remote access by ISDN and PSTN networks. This document augments the procedures described in {[}RFC2661{]} to further support ATM SVC or PVC based access networks. The extensions defined within this document allow for asymmetric bi-directional call establishment and service selection in the ATM access network.},
}