%% You should probably cite rfc8915 instead of this I-D.
@techreport{ietf-ntp-using-nts-for-ntp-01,
    number =    {draft-ietf-ntp-using-nts-for-ntp-01},
    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-ntp-using-nts-for-ntp/01/},
    author =    {Dieter Sibold and Stephen Roettger and Kristof Teichel},
    title =     {{Using the Network Time Security Specification to Secure the Network Time Protocol}},
    pagetotal = 17,
    year =      2015,
    month =     jul,
    day =       6,
    abstract =  {This document describes how to use the measures described in the Network Time Security (NTS) specification to secure time synchronization with servers using the Network Time Protocol (NTP).},
}