Cryptology ePrint Archive: BibTeX Citation of Report 2013/634

@misc{cryptoeprint:2013:634,
    author = {Itai Dinur and Orr Dunkelman and Nathan Keller and Adi Shamir},
    title = {Improved Linear Sieving Techniques with Applications to Step-Reduced LED-64},
    howpublished = {Cryptology ePrint Archive, Report 2013/634},
    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.