@misc{cryptoeprint:2009:148,
author = {Yutaka Kawai and Kazuki Yoneyama and Kazuo Ohta},
title = {Secret Handshake: Strong Anonymity Definition and Construction},
howpublished = {Cryptology ePrint Archive, Report 2009/148},
year = {2009},
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.