@misc{cryptoeprint:2014:195,
author = {Dan Boneh and Brent Waters and Mark Zhandry},
title = {Low Overhead Broadcast Encryption from Multilinear Maps},
howpublished = {Cryptology ePrint Archive, Report 2014/195},
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.