%% You should probably cite draft-ietf-core-coap-tcp-tls instead of this I-D.
@techreport{savolainen-core-coap-websockets-02,
    number =    {draft-savolainen-core-coap-websockets-02},
    type =      {Internet-Draft},
    institution =   {Internet Engineering Task Force},
    publisher = {Internet Engineering Task Force},
    note =      {Work in Progress},
    url =       {https://datatracker.ietf.org/doc/draft-savolainen-core-coap-websockets/02/},
    author =    {Teemu Savolainen and Klaus Hartke and Bill Silverajan},
    title =     {{CoAP over WebSockets}},
    pagetotal = 17,
    year =      2014,
    month =     apr,
    day =       10,
    abstract =  {This document specifies how to retrieve and update CoAP resources using CoAP requests and responses over the WebSocket Protocol.},
}