@misc{cryptoeprint:2009:351,
author = {David Cash and Dennis Hofheinz and Eike Kiltz },
title = {How to Delegate a Lattice Basis},
howpublished = {Cryptology ePrint Archive, Report 2009/351},
year = {2009},
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.