%% You should probably cite rfc4087 instead of this I-D.
@techreport{ietf-ipv6-inet-tunnel-mib-03,
    number =    {draft-ietf-ipv6-inet-tunnel-mib-03},
    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-ipv6-inet-tunnel-mib/03/},
    author =    {Dave Thaler},
    title =     {{IP Tunnel MIB}},
    pagetotal = 25,
    year =      2004,
    month =     oct,
    day =       20,
    abstract =  {This memo defines a Management Information Base (MIB) module for use with network management protocols in the Internet community. In particular, it describes managed objects used for managing tunnels of any type over IPv4 and IPv6 networks. Extension MIB modules may be designed for managing protocol-specific objects. Likewise, extension MIB modules may be designed for managing security-specific objects. This MIB module does not support tunnels over non-IP networks. Management of such tunnels may be supported by other MIB modules. This memo obsoletes RFC 2667. {[}STANDARDS-TRACK{]}},
}