%% You should probably cite rfc7040 instead of this I-D.
@techreport{ietf-softwire-public-4over6-00,
    number =    {draft-ietf-softwire-public-4over6-00},
    type =      {Internet-Draft},
    institution =   {Internet Engineering Task Force},
    publisher = {Internet Engineering Task Force},
    note =      {Work in Progress},
    url =       {https://datatracker.ietf.org/doc/draft-ietf-softwire-public-4over6/00/},
    author =    {Yong Cui and Jianping Wu and Peng Wu and Chris Metz and Olivier Vautrin and Yiu Lee},
    title =     {{Public IPv4 over Access IPv6 Network}},
    pagetotal = 13,
    year =      2011,
    month =     sep,
    day =       8,
    abstract =  {This draft proposes a mechanism for bidirectional IPv4 communication between IPv4 Internet and end hosts or IPv4 networks sited in IPv6 access network. This mechanism follows the softwire hub and spoke model and uses IPv4-over-IPv6 tunnel as basic method to traverse IPv6 network. By allocating public IPv4 addresses to end hosts/networks in IPv6, it can achieve IPv4 end-to-end bidirectional communication between these hosts/networks and IPv4 Internet. This mechanism is an IPv4 access method for hosts and IPv4 networks sited in IPv6.},
}