Cryptology ePrint Archive: BibTeX Citation of Report 2012/236

@misc{cryptoeprint:2012:236,
    author = {D. Bernhard and O. Pereira and B. Warinschi},
    title = {On Necessary and Sufficient Conditions for Private Ballot Submission},
    howpublished = {Cryptology ePrint Archive, Report 2012/236},
    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.