@misc{cryptoeprint:2007:167,
    author = {Yi-Ru Liu, Wen-Guey Tzeng},
    title = {Public Key Broadcast Encryption with Low Number of Keys and Constant Decryption Time (Version 2)},
    howpublished = {Cryptology ePrint Archive, Report 2007/167},
    year = {2007},
    url = {http://eprint.iacr.org/2007/167},
}