%% You should probably cite draft-ietf-pim-dr-improvement instead of this I-D.
@techreport{zhang-pim-dr-improvement-01,
    number =    {draft-zhang-pim-dr-improvement-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-zhang-pim-dr-improvement/01/},
    author =    {Zheng Zhang and fangwei hu and BenChong Xu},
    title =     {{PIM DR Improvement}},
    pagetotal = 7,
    year =      2016,
    month =     jan,
    day =       21,
    abstract =  {PIM is worldly deployed multicast protocol. This document will improve the stability of PIM protocol, decrease the lost of multicast packets when the PIM DR (Designed Router) is down.},
}