%% You should probably cite draft-ietf-ace-coap-est instead of this I-D.
@techreport{vanderstok-ace-coap-est-04,
    number =    {draft-vanderstok-ace-coap-est-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-vanderstok-ace-coap-est/04/},
    author =    {Peter Van der Stok and Panos Kampanakis and Sandeep S. Kumar and Michael Richardson and Martin Furuhed and Shahid Raza},
    title =     {{EST over secure CoAP (EST-coaps)}},
    pagetotal = 30,
    year =      2018,
    month =     jan,
    day =       22,
    abstract =  {Enrollment over Secure Transport (EST) {[}RFC7030{]} is used as a certificate management protocol over HTTPS. Low-resource devices often use the lightweight Constrained Application Protocol (CoAP) {[}RFC7252{]} for message exchanges. This document defines how to transport EST payloads over secure CoAP (EST- coaps). This allows low-resource constrained devices to re-use existing EST functionality. Example low-resource use cases for EST are: secure bootstrapping and certificate enrollment.},
}