@misc{cryptoeprint:2015:360,
author = {Yanqing Yao, Zhoujun Li},
title = {Achieving Differential Privacy with Bias-Control Limited Source},
howpublished = {Cryptology ePrint Archive, Report 2015/360},
year = {2015},
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.