%% You should probably cite rfc8555 instead of this I-D.
@techreport{ietf-acme-acme-18,
    number =    {draft-ietf-acme-acme-18},
    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-acme/18/},
    author =    {Richard Barnes and Jacob Hoffman-Andrews and Daniel McCarney and James Kasten},
    title =     {{Automatic Certificate Management Environment (ACME)}},
    pagetotal = 95,
    year =      2018,
    month =     dec,
    day =       20,
    abstract =  {Public Key Infrastructure using X.509 (PKIX) certificates are used for a number of purposes, the most significant of which is the authentication of domain names. Thus, certification authorities (CAs) in the Web PKI are trusted to verify that an applicant for a certificate legitimately represents the domain name(s) in the certificate. As of this writing, this verification is done through a collection of ad hoc mechanisms. This document describes a protocol that a CA and an applicant can use to automate the process of verification and certificate issuance. The protocol also provides facilities for other certificate management functions, such as certificate revocation.},
}