@misc{cryptoeprint:2009:284,
    author = {Jin Li,  Kui Ren, Bo Zhu, and Zhiguo Wan},
    title = {Privacy-aware Attribute-based Encryption with User Accountability},
    howpublished = {Cryptology ePrint Archive, Report 2009/284},
    year = {2009},
    url = {http://eprint.iacr.org/2009/284},
}