@misc{cryptoeprint:2014:794,
author = {Léo Ducas and Vadim Lyubashevsky and Thomas Prest},
title = {Efficient Identity-Based Encryption over NTRU Lattices},
howpublished = {Cryptology ePrint Archive, Report 2014/794},
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.