@misc{cryptoeprint:2008:196,
author = {Zhengbang Zha and Gohar M. Kyureghyan and Xueli Wang},
title = {A New Family of Perfect Nonlinear Binomials},
howpublished = {Cryptology ePrint Archive, Report 2008/196},
year = {2008},
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.