Cryptology ePrint Archive: BibTeX Citation of Report 2011/528

@misc{cryptoeprint:2011:528,
    author = {Jian-Zhu Lu, Hong-Qing Ren, and Jipeng Zhou},
    title = {Efficient Delegation-Based Authentication Protocol with Strong Mobile Privacy},
    howpublished = {Cryptology ePrint Archive, Report 2011/528},
    year = {2011},
    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.