%% You should probably cite rfc8228 instead of this I-D.
@techreport{freytag-lager-variant-rules-01,
    number =    {draft-freytag-lager-variant-rules-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-freytag-lager-variant-rules/01/},
    author =    {Asmus Freytag},
    title =     {{Variant Rules}},
    pagetotal = 18,
    year =      2016,
    month =     dec,
    day =       27,
    abstract =  {This document gives guidance on designing well-behaved Label Generation Rulesets (LGRs) that support variant labels. Typical examples of labels and LGRs are IDNs and zone registration policies defining permissible IDN labels. Variant labels are labels that are either visually or semantically indistinguishable from an applied for label and are typically delegated together with the applied-for label, or permanently reserved. While {[}RFC7940{]} defines the syntactical requirements for specifying the label generation rules for variant labels, additional considerations apply that ensure that the label generation rules are consistent and well-behaved in the presence of variants.},
}