%% You should probably cite draft-xibassnez-i2nsf-capability instead of this I-D.
@techreport{xia-i2nsf-capability-interface-im-06,
    number =    {draft-xia-i2nsf-capability-interface-im-06},
    type =      {Internet-Draft},
    institution =   {Internet Engineering Task Force},
    publisher = {Internet Engineering Task Force},
    note =      {Work in Progress},
    url =       {https://datatracker.ietf.org/doc/draft-xia-i2nsf-capability-interface-im/06/},
    author =    {Liang Xia and John Strassner and Kepeng Li and Dacheng Zhang and Edward Lopez and Nicolas Bouthors and Luyuan Fang},
    title =     {{Information Model of Interface to Network Security Functions Capability Interface}},
    pagetotal = 55,
    year =      2016,
    month =     jul,
    day =       1,
    abstract =  {This draft is focused on the capability interface of NSFs (Network Security Functions) and proposes its information model for managing the various network security functions.},
}