%% You should probably cite rfc8824 instead of this I-D.
@techreport{ietf-lpwan-coap-static-context-hc-09,
    number =    {draft-ietf-lpwan-coap-static-context-hc-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-lpwan-coap-static-context-hc/09/},
    author =    {Ana Minaburo and Laurent Toutain and Ricardo Andreasen},
    title =     {{LPWAN Static Context Header Compression (SCHC) for CoAP}},
    pagetotal = 28,
    year =      2019,
    month =     jul,
    day =       6,
    abstract =  {This draft defines the way SCHC header compression can be applied to CoAP headers. The CoAP header structure differs from IPv6 and UDP protocols since CoAP uses a flexible header with a variable number of options, themselves of variable length. The CoAP protocol is asymmetric in its message format: the format of the packet header in the request messages is different from that in the response messages. Most of the compression mechanisms have been introduced in {[}I-D.ietf-lpwan-ipv6-static-context-hc{]}, this document explains how to use the SCHC compression for CoAP.},
}