@misc{cryptoeprint:2012:207,
    author = {Kai Zhang, Lin Ding and Jie Guan},
    title = {Cryptanalysis of Hummingbird-2},
    howpublished = {Cryptology ePrint Archive, Report 2012/207},
    year = {2012},
    url = {http://eprint.iacr.org/2012/207},
}