@misc{rfc4407,
    series =    {Request for Comments},
    number =    4407,
    howpublished =  {RFC 4407},
    publisher = {RFC Editor},
    doi =       {10.17487/RFC4407},
    url =       {https://www.rfc-editor.org/info/rfc4407},
    author =    {Jim Lyon},
    title =     {{Purported Responsible Address in E-Mail Messages}},
    pagetotal = 7,
    year =      2006,
    month =     apr,
    abstract =  {This document defines an algorithm by which, given an e-mail message, one can extract the identity of the party that appears to have most proximately caused that message to be delivered. This identity is called the Purported Responsible Address (PRA).This memo defines an Experimental Protocol for the Internet community.},
}