@misc{cryptoeprint:2011:498,
author = {*Jue-Sam Chou 1, Shih-Che Hung 2, Yalin Chen},
title = {An Efficient Secure Anonymous Proxy Signature Scheme},
howpublished = {Cryptology ePrint Archive, Report 2011/498},
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.