@misc{cryptoeprint:2011:176,
author = {Sylvain Duquesne and Nicolas Guillermin},
title = {A FPGA pairing implementation using the Residue Number System},
howpublished = {Cryptology ePrint Archive, Report 2011/176},
year = {2011},
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.