@misc{cryptoeprint:2012:195,
author = {Markku-Juhani O. Saarinen },
title = {The BlueJay Ultra-Lightweight Hybrid Cryptosystem },
howpublished = {Cryptology ePrint Archive, Report 2012/195},
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.