@misc{cryptoeprint:2005:450,
author = {Jue-Sam Chou, Yalin Chen, Jyun-Yu Lin},
title = {Improvement of Manik et al.¡¦s remote user authentication scheme},
howpublished = {Cryptology ePrint Archive, Report 2005/450},
year = {2005},
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.