%% You should probably cite rfc5331 instead of this I-D.
@techreport{ietf-mpls-upstream-label-07,
    number =    {draft-ietf-mpls-upstream-label-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-mpls-upstream-label/07/},
    author =    {Yakov Rekhter and Rahul Aggarwal and Eric C. Rosen},
    title =     {{MPLS Upstream Label Assignment and Context-Specific Label Space}},
    pagetotal = 13,
    year =      2008,
    month =     jul,
    day =       10,
    abstract =  {RFC 3031 limits the MPLS architecture to downstream-assigned MPLS labels. This document introduces the notion of upstream-assigned MPLS labels. It describes the procedures for upstream MPLS label assignment and introduces the concept of a "Context-Specific Label Space". {[}STANDARDS-TRACK{]}},
}