@misc{cryptoeprint:2004:138,
author = {Benoit Chevallier-Mames and David Naccache and Pascal Paillier and David Pointcheval},
title = {How to Disembed a Program?},
howpublished = {Cryptology ePrint Archive, Report 2004/138},
year = {2004},
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.