%% You should probably cite draft-ietf-core-multipart-ct instead of this I-D.
@techreport{fossati-core-multipart-ct-04,
    number =    {draft-fossati-core-multipart-ct-04},
    type =      {Internet-Draft},
    institution =   {Internet Engineering Task Force},
    publisher = {Internet Engineering Task Force},
    note =      {Work in Progress},
    url =       {https://datatracker.ietf.org/doc/draft-fossati-core-multipart-ct/04/},
    author =    {Carsten Bormann},
    title =     {{Multipart Content-Format for CoAP}},
    pagetotal = 5,
    year =      2018,
    month =     jun,
    day =       5,
    abstract =  {This memo defines multipart/core, an application-independent media- type that can be used to combine (even recursively) several different media types into a single CoAP message-body with minimal framing overhead, along with a CoAP Content-Format identifier.},
}