@misc{cryptoeprint:2012:708,
author = {Gilad Asharov and Claudio Orlandi},
title = {Calling out Cheaters: Covert Security With Public Verifiability},
howpublished = {Cryptology ePrint Archive, Report 2012/708},
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.