@misc{cryptoeprint:2006:361,
author = {Sherman S.M. Chow and Willy Susilo},
title = {Generic Construction of (Identity-based) Perfect Concurrent Signatures},
howpublished = {Cryptology ePrint Archive, Report 2006/361},
year = {2006},
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.