@misc{cryptoeprint:2015:299,
author = {Zhengjun Cao and Lihua Liu},
title = {A Note on the Lindell-Waisbard Private Web Search Scheme},
howpublished = {Cryptology ePrint Archive, Report 2015/299},
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.