Cryptology ePrint Archive: BibTeX Citation of Report 2015/431

@misc{cryptoeprint:2015:431,
    author = {Nuttapong Attrapadung and Goichiro Hanaoka and Shota Yamada},
    title = {Conversions among Several Classes of Predicate Encryption and Applications to ABE with Various Compactness Tradeoffs},
    howpublished = {Cryptology ePrint Archive, Report 2015/431},
    year = {2015},
    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.