%% You should probably cite rfc2693 instead of this I-D.
@techreport{ietf-spki-cert-theory-05,
    number =    {draft-ietf-spki-cert-theory-05},
    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-spki-cert-theory/05/},
    author =    {Tatu Ylonen and Brian Thomas and Butler Lampson and Carl Ellison and Ronald L. Rivest and William S. Frantz},
    title =     {{SPKI Certificate Theory}},
    pagetotal = 43,
    year =      1999,
    month =     jun,
    day =       1,
    abstract =  {This document gives the theory behind SPKI certificates and ACLs without going into technical detail about those structures or their uses. This memo defines an Experimental Protocol for the Internet community.},
}