%% You should probably cite rfc7761 instead of this I-D.
@techreport{ietf-pim-rfc4601bis-06,
    number =    {draft-ietf-pim-rfc4601bis-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-pim-rfc4601bis/06/},
    author =    {Bill Fenner (ˢˣˠ) and Mark J. Handley and Hugh Holbrook and Isidor Kouvelas and Rishabh Parekh and Zhaohui (Jeffrey) Zhang and Lianshu Zheng},
    title =     {{Protocol Independent Multicast - Sparse Mode (PIM-SM): Protocol Specification (Revised)}},
    pagetotal = 137,
    year =      2015,
    month =     aug,
    day =       12,
    abstract =  {This document specifies Protocol Independent Multicast - Sparse Mode (PIM-SM). PIM-SM is a multicast routing protocol that can use the underlying unicast routing information base or a separate multicast-capable routing information base. It builds unidirectional shared trees rooted at a Rendezvous Point (RP) per group, and it optionally creates shortest-path trees per source. This document obsoletes RFC 4601 by replacing it, addresses the errata filed against it, removes the optional (*,*,RP), PIM Multicast Border Router features and authentication using IPsec that lack sufficient deployment experience (see Appendix A), and moves the PIM specification to Internet Standard.},
}