%% You should probably cite draft-ietf-ntp-alternative-port instead of this I-D.
@techreport{mlichvar-ntp-alternative-port-01,
    number =    {draft-mlichvar-ntp-alternative-port-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-mlichvar-ntp-alternative-port/01/},
    author =    {Miroslav Lichvar},
    title =     {{Alternative NTP port}},
    pagetotal = 5,
    year =      2020,
    month =     jun,
    day =       9,
    abstract =  {This document specifies an alternative port for the Network Time Protocol (NTP) which is restricted in the supported modes and extensions to not allow traffic amplification in order to make NTP safe for the Internet.},
}