%% You should probably cite draft-ietf-enum-validation-token instead of this I-D.
@techreport{lendl-enum-validation-token-00,
    number =    {draft-lendl-enum-validation-token-00},
    type =      {Internet-Draft},
    institution =   {Internet Engineering Task Force},
    publisher = {Internet Engineering Task Force},
    note =      {Work in Progress},
    url =       {https://datatracker.ietf.org/doc/draft-lendl-enum-validation-token/00/},
    author =    {Otmar Lendl},
    title =     {{ENUM Validation Token Format Definition}},
    pagetotal = 16,
    year =      2005,
    month =     jul,
    day =       11,
    abstract =  {An ENUM domain name is tightly coupled with the underlying E.164 number. The process of verifying whether the Registrant of an ENUM domain name is identical to the Assignee of the corresponding E.164 number is commonly called "validation". This document describes an signed XML data format -- the Validation Token -- with which Validation Entities can convey successful completion of a validation procedure in a secure fashion.},
}