%% You should probably cite rfc8228 instead of this I-D.
@techreport{freytag-lager-variant-rules-05,
    number =    {draft-freytag-lager-variant-rules-05},
    type =      {Internet-Draft},
    institution =   {Internet Engineering Task Force},
    publisher = {Internet Engineering Task Force},
    note =      {Work in Progress},
    url =       {https://datatracker.ietf.org/doc/draft-freytag-lager-variant-rules/05/},
    author =    {Asmus Freytag},
    title =     {{Variant Rules}},
    pagetotal = 23,
    year =      2017,
    month =     apr,
    day =       14,
    abstract =  {Rules for validating identifier labels and alternate representations of those labels (variants) are known as "Label Generation Rulesets" (LGRs); they are used for the implementation of identifier systems such as Internationalized Domain Names (IDNs). This document describes ways of designing Label Generation Rulesets (LGRs) that support variant labels. In designing LGRs, it is important to ensure that the label generation rules are consistent and well-behaved in the presence of variants. The design decisions can then be expressed using the XML representation of LGRs that is defined in RFC7940.},
}