Cryptology ePrint Archive: BibTeX Citation of Report 2006/431

@misc{cryptoeprint:2006:431,
    author = {Masaaki Shirase and Tsuyoshi Takagi and Eiji Okamoto},
    title = {Some Efficient Algorithms for the Final Exponentiation of $\eta_T$ Pairing},
    howpublished = {Cryptology ePrint Archive, Report 2006/431},
    year = {2006},
    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.