%% You should probably cite rfc4954 instead of this I-D.
@techreport{siemborski-rfc2554bis-09,
    number =    {draft-siemborski-rfc2554bis-09},
    type =      {Internet-Draft},
    institution =   {Internet Engineering Task Force},
    publisher = {Internet Engineering Task Force},
    note =      {Work in Progress},
    url =       {https://datatracker.ietf.org/doc/draft-siemborski-rfc2554bis/09/},
    author =    {Rob Siemborski and Alexey Melnikov},
    title =     {{SMTP Service Extension for Authentication}},
    pagetotal = 20,
    year =      2007,
    month =     apr,
    day =       3,
    abstract =  {This document defines a Simple Mail Transport Protocol (SMTP) extension whereby an SMTP client may indicate an authentication mechanism to the server, perform an authentication protocol exchange, and optionally negotiate a security layer for subsequent protocol interactions during this session. This extension includes a profile of the Simple Authentication and Security Layer (SASL) for SMTP. This document obsoletes RFC 2554. {[}STANDARDS-TRACK{]}},
}