@misc{cryptoeprint:2012:330,
author = {Xu ZiJie and Xu Ke},
title = {A Way Reduce Signed Bitwise Differences that Transformed Into Same Modular Differences},
howpublished = {Cryptology ePrint Archive, Report 2012/330},
year = {2012},
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.