%% You should probably cite rfc2446 instead of this I-D.
@techreport{ietf-calsch-itip-06,
    number =    {draft-ietf-calsch-itip-06},
    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-calsch-itip/06/},
    author =    {Frank Dawson and Ross Hopson and Steve Mansour and Steve Silverberg},
    title =     {{iCalendar Transport-Independent Interoperability Protocol (iTIP) Scheduling Events, BusyTime, To-dos and Journal Entries}},
    pagetotal = 109,
    year =      1998,
    month =     sep,
    day =       22,
    abstract =  {This document specifies how calendaring systems use iCalendar objects to interoperate with other calendar systems. It does so in a general way so as to allow multiple methods of communication between systems. {[}STANDARDS-TRACK{]}},
}