%% You should probably cite rfc5724 instead of this I-D.
@techreport{wilde-sms-uri-20,
    number =    {draft-wilde-sms-uri-20},
    type =      {Internet-Draft},
    institution =   {Internet Engineering Task Force},
    publisher = {Internet Engineering Task Force},
    note =      {Work in Progress},
    url =       {https://datatracker.ietf.org/doc/draft-wilde-sms-uri/20/},
    author =    {Antti Vaha-Sipila and Erik Wilde},
    title =     {{URI Scheme for Global System for Mobile Communications (GSM) Short Message Service (SMS)}},
    pagetotal = 18,
    year =      2009,
    month =     oct,
    day =       23,
    abstract =  {This memo specifies the Uniform Resource Identifier (URI) scheme "sms" for specifying one or more recipients for an SMS message. SMS messages are two-way paging messages that can be sent from and received by a mobile phone or a suitably equipped networked device. {[}STANDARDS-TRACK{]}},
}