@misc{cryptoeprint:2004:226,
    author = {Boaz Barak and Yehuda Lindell and Salil Vadhan},
    title = {Lower Bounds for Non-Black-Box Zero Knowledge},
    howpublished = {Cryptology ePrint Archive, Report 2004/226},
    year = {2004},
    url = {http://eprint.iacr.org/2004/226},
}