%% You should probably cite rfc5194 instead of this I-D.
@techreport{ietf-sipping-toip-09,
    number =    {draft-ietf-sipping-toip-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-ietf-sipping-toip/09/},
    author =    {Guido Gybels and Arnoud Wijk},
    title =     {{Framework for Real-Time Text over IP Using the Session Initiation Protocol (SIP)}},
    pagetotal = 31,
    year =      2008,
    month =     apr,
    day =       4,
    abstract =  {This document lists the essential requirements for real-time Text-over-IP (ToIP) and defines a framework for implementation of all required functions based on the Session Initiation Protocol (SIP) and the Real-Time Transport Protocol (RTP). This includes interworking between Text-over-IP and existing text telephony on the Public Switched Telephone Network (PSTN) and other networks. This memo provides information for the Internet community.},
}