@misc{cryptoeprint:2015:722,
author = {Tarik Moataz and Erik-Oliver Blass},
title = {Oblivious Substring Search with Updates},
howpublished = {Cryptology ePrint Archive, Report 2015/722},
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.