Cryptology ePrint Archive: BibTeX Citation of Report 2012/484

@misc{cryptoeprint:2012:484,
    author = {Ding Wang, Chun-guang Ma, De-li Gu and Zhen-shan Cui},
    title = {Cryptanalysis of Two Dynamic ID-based Remote User Authentication Schemes for Multi-Server Architecture},
    howpublished = {Cryptology ePrint Archive, Report 2012/484},
    year = {2012},
    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.