@misc{cryptoeprint:2014:604,
author = {Bolam Kang and Sung Cheol Goh and Myungsun Kim},
title = {Private Web Search with Constant Round Efficiency},
howpublished = {Cryptology ePrint Archive, Report 2014/604},
year = {2014},
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.