Cryptology ePrint Archive: BibTeX Citation of Report 2012/193

@misc{cryptoeprint:2012:193,
    author = {Liangliang Xiao and Osbert Bastani and I-Ling Yen},
    title = {An Efficient Homomorphic Encryption Protocol  for Multi-User Systems},
    howpublished = {Cryptology ePrint Archive, Report 2012/193},
    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.