@misc{cryptoeprint:2013:450,
author = {Yoni De Mulder and Peter Roelse and Bart Preneel},
title = {Revisiting the BGE Attack on a White-Box AES Implementation},
howpublished = {Cryptology ePrint Archive, Report 2013/450},
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.