@misc{cryptoeprint:2003:259,
    author = {Fangguo Zhang and Xiaofeng Chen},
    title = {Attack on Two ID-based Authenticated Group Key Agreement Schemes},
    howpublished = {Cryptology ePrint Archive, Report 2003/259},
    year = {2003},
    url = {http://eprint.iacr.org/2003/259},
}