@misc{cryptoeprint:2014:509,
author = {Kaoutar Elkhiyaoui and Melek Onen and Refik Molva},
title = {Privacy preserving delegated word search in the cloud},
howpublished = {Cryptology ePrint Archive, Report 2014/509},
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.