@misc{cryptoeprint:2003:207,
    author = {Guilin Wang, and Sihan Qing},
    title = {Security Flaws in Several Group Signatures Proposed by Popescu},
    howpublished = {Cryptology ePrint Archive, Report 2003/207},
    year = {2003},
    url = {http://eprint.iacr.org/2003/207},
}