Cryptology ePrint Archive: BibTeX Citation of Report 2011/215

@misc{cryptoeprint:2011:215,
    author = {M. Barbosa and P. Farshim},
    title = {Delegatable Homomorphic Encryption with Applications to Secure Outsourcing of Computation},
    howpublished = {Cryptology ePrint Archive, Report 2011/215},
    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.