@misc{cryptoeprint:2003:068,
    author = {Hung-Min Sun and Bin-Tsan Hsieh},
    title = {On the Security of Some Proxy Signature Schemes},
    howpublished = {Cryptology ePrint Archive, Report 2003/068},
    year = {2003},
    url = {http://eprint.iacr.org/2003/068},
}