@misc{cryptoeprint:2012:673,
author = {Pooya Farshim and Benoît Libert and Kenneth G. Paterson and Elizabeth A. Quaglia},
title = {Robust Encryption, Revisited},
howpublished = {Cryptology ePrint Archive, Report 2012/673},
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.