@techreport{procter-bliss-call-park-extension-05,
    number =    {draft-procter-bliss-call-park-extension-05},
    type =      {Internet-Draft},
    institution =   {Internet Engineering Task Force},
    publisher = {Internet Engineering Task Force},
    note =      {Work in Progress},
    url =       {https://datatracker.ietf.org/doc/draft-procter-bliss-call-park-extension/05/},
    author =    {Michael Procter},
    title =     {{Implementing Call Park and Retrieve using the Session Initiation Protocol (SIP)}},
    pagetotal = 19,
    year =      2009,
    month =     jun,
    day =       8,
    abstract =  {Call Park and Call Retrieve are useful telephony services that are familiar to many users. Existing implementations using the Session Initiation Protocol (SIP) show that a variety of approaches can be taken, with varying degrees of interoperability. This draft discusses a number of feature variations, and how they may be implemented using existing techniques. An additional URI parameter is also described, which enables further common use-cases to be implemented.},
}