@misc{cryptoeprint:2013:845,
author = {Aggelos Kiayias and Qiang Tang},
title = {How to Keep a Secret: Leakage Deterring Public-key Cryptography},
howpublished = {Cryptology ePrint Archive, Report 2013/845},
year = {2013},
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.