%% You should probably cite rfc9447 instead of this I-D.
@techreport{ietf-acme-authority-token-06,
    number =    {draft-ietf-acme-authority-token-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-acme-authority-token/06/},
    author =    {Jon Peterson and Mary Barnes and David Hancock and Chris Wendt},
    title =     {{ACME Challenges Using an Authority Token}},
    pagetotal = 11,
    year =      2021,
    month =     jul,
    day =       12,
    abstract =  {Some proposed extensions to the Automated Certificate Management Environment (ACME) rely on proving eligibility for certificates through consulting an external authority that issues a token according to a particular policy. This document specifies a generic Authority Token challenge for ACME which supports subtype claims for different identifiers or namespaces that can be defined separately for specific applications.},
}