%% You should probably cite rfc8168 instead of this I-D.
@techreport{ietf-dhc-dhcpv6-prefix-length-hint-issue-06,
    number =    {draft-ietf-dhc-dhcpv6-prefix-length-hint-issue-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-ietf-dhc-dhcpv6-prefix-length-hint-issue/06/},
    author =    {Tianxiang Li and Cong Liu and Yong Cui},
    title =     {{DHCPv6 Prefix-Length Hint Issues}},
    pagetotal = 9,
    year =      2017,
    month =     mar,
    day =       31,
    abstract =  {DHCPv6 Prefix Delegation allows a client to include a prefix-length hint value in the IA\_PD option to indicate a preference for the size of the prefix to be delegated, but it is unclear about how the client and server should act in different situations involving the prefix-length hint. This document provides a summary of the existing problems with the prefix-length hint and guidance on what the client and server could do in different situations.},
}