%% You should probably cite draft-ietf-clue-data-model-schema instead of this I-D.
@techreport{presta-clue-data-model-schema-02,
    number =    {draft-presta-clue-data-model-schema-02},
    type =      {Internet-Draft},
    institution =   {Internet Engineering Task Force},
    publisher = {Internet Engineering Task Force},
    note =      {Work in Progress},
    url =       {https://datatracker.ietf.org/doc/draft-presta-clue-data-model-schema/02/},
    author =    {Roberta Presta and Simon Pietro Romano},
    title =     {{An XML Schema for the CLUE data model}},
    pagetotal = 21,
    year =      2013,
    month =     feb,
    day =       2,
    abstract =  {This document provides an XML schema file for the definition of CLUE data model types.},
}