@misc{cryptoeprint:2012:587,
    author = {Changyong Peng and Chuangying zhu and Yuefei Zhu and Fei Kang},
    title = {Symbolic computation in block cipher with application to PRESENT},
    howpublished = {Cryptology ePrint Archive, Report 2012/587},
    year = {2012},
    url = {http://eprint.iacr.org/2012/587},
}