@misc{cryptoeprint:2010:307,
    author = {Ruilin Li and Bing Sun and Chao Li},
    title = {Impossible Differential Cryptanalysis of SPN Ciphers},
    howpublished = {Cryptology ePrint Archive, Report 2010/307},
    year = {2010},
    url = {http://eprint.iacr.org/2010/307},
}