@misc{cryptoeprint:2008:347,
author = {Chengfang Fang and Ee-Chien Chang},
title = {Information Leakage in Optimal Anonymized and Diversified Data},
howpublished = {Cryptology ePrint Archive, Report 2008/347},
year = {2008},
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.