@misc{rfc3857,
    series =    {Request for Comments},
    number =    3857,
    howpublished =  {RFC 3857},
    publisher = {RFC Editor},
    doi =       {10.17487/RFC3857},
    url =       {https://www.rfc-editor.org/info/rfc3857},
    author =    {Jonathan Rosenberg},
    title =     {{A Watcher Information Event Template-Package for the Session Initiation Protocol (SIP)}},
    pagetotal = 20,
    year =      2004,
    month =     aug,
    abstract =  {This document defines the watcher information template-package for the Session Initiation Protocol (SIP) event framework. Watcher information refers to the set of users subscribed to a particular resource within a particular event package. Watcher information changes dynamically as users subscribe, unsubscribe, are approved, or are rejected. A user can subscribe to this information, and therefore learn about changes to it. This event package is a template-package because it can be applied to any event package, including itself. {[}STANDARDS-TRACK{]}},
}