Cryptology ePrint Archive: BibTeX Citation of Report 2009/420

@misc{cryptoeprint:2009:420,
    author = {Matthieu Rivain and Emmanuel Prouff and Julien Doget},
    title = {Higher-order Masking and Shuffling for Software Implementations of Block Ciphers},
    howpublished = {Cryptology ePrint Archive, Report 2009/420},
    year = {2009},
    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.