Cryptology ePrint Archive: BibTeX Citation of Report 2008/478

@misc{cryptoeprint:2008:478,
    author = {M. J. Hinek and S. Jiang and R. Safavi-Naini and S. F. Shahandashti},
    title = {Attribute-Based Encryption with Key Cloning Protection},
    howpublished = {Cryptology ePrint Archive, Report 2008/478},
    year = {2008},
    note = {\url{http://eprint.iacr.org/}},
}

You will need the url.sty package (comes with most LaTeX installations) for the last line. Otherwise, remove the \url command.