Cryptology ePrint Archive: BibTeX Citation of Report 2013/422

@misc{cryptoeprint:2013:422,
    author = {Dan Boneh and Craig Gentry and Shai Halevi and Frank Wang and David J. Wu},
    title = {Private Database Queries Using Somewhat Homomorphic Encryption},
    howpublished = {Cryptology ePrint Archive, Report 2013/422},
    year = {2013},
    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.