@misc{cryptoeprint:2013:512,
author = {Jingguo Bi and Phong Q. Nguyen},
title = {Rounding LLL: Finding Faster Small Roots of Univariate Polynomial Congruences },
howpublished = {Cryptology ePrint Archive, Report 2013/512},
year = {2013},
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.