%% You should probably cite rfc8099 instead of this I-D.
@techreport{ietf-ospf-ttz-06,
    number =    {draft-ietf-ospf-ttz-06},
    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-ospf-ttz/06/},
    author =    {Huaimo Chen and Richard Li and Alvaro Retana and Yi Yang and Vic Liu},
    title =     {{OSPF Topology-Transparent Zone}},
    pagetotal = 27,
    year =      2017,
    month =     jan,
    day =       8,
    abstract =  {This document presents a Topology-Transparent Zone (TTZ) in an OSPF area. A TTZ comprises a group of routers and a number of links connecting these routers. Any router outside of the zone is not aware of the zone. A TTZ hides the internal topology of the TTZ from the outside. It does not directly advertise any internal information about the TTZ to a router outside of the TTZ. The information about the links and routers such as a link down inside the TTZ is not advertised to any router outside of the TTZ.},
}