@misc{rfc8551,
    series =    {Request for Comments},
    number =    8551,
    howpublished =  {RFC 8551},
    publisher = {RFC Editor},
    doi =       {10.17487/RFC8551},
    url =       {https://www.rfc-editor.org/info/rfc8551},
    author =    {Jim Schaad and Blake C. Ramsdell and Sean Turner},
    title =     {{Secure/Multipurpose Internet Mail Extensions (S/MIME) Version 4.0 Message Specification}},
    pagetotal = 63,
    year =      2019,
    month =     apr,
    abstract =  {This document defines Secure/Multipurpose Internet Mail Extensions (S/MIME) version 4.0. S/MIME provides a consistent way to send and receive secure MIME data. Digital signatures provide authentication, message integrity, and non-repudiation with proof of origin. Encryption provides data confidentiality. Compression can be used to reduce data size. This document obsoletes RFC 5751.},
}