%% You should probably cite rfc4894 instead of this I-D.
@techreport{hoffman-ike-ipsec-hash-use-06,
    number =    {draft-hoffman-ike-ipsec-hash-use-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-hoffman-ike-ipsec-hash-use/06/},
    author =    {Paul E. Hoffman},
    title =     {{Use of Hash Algorithms in Internet Key Exchange (IKE) and IPsec}},
    pagetotal = 11,
    year =      2007,
    month =     mar,
    day =       5,
    abstract =  {This document describes how the IKEv1 (Internet Key Exchange version 1), IKEv2, and IPsec protocols use hash functions, and explains the level of vulnerability of these protocols to the reduced collision resistance of the MD5 and SHA-1 hash algorithms. This memo provides information for the Internet community.},
}