@misc{cryptoeprint:2007:339,
    author = {Chengqing Li and Guanrong Chen},
    title = {On the security of a class of image encryption schemes},
    howpublished = {Cryptology ePrint Archive, Report 2007/339},
    year = {2007},
    url = {http://eprint.iacr.org/2007/339},
}