Cryptology ePrint Archive: BibTeX Citation of Report 2007/104

@misc{cryptoeprint:2007:104,
    author = {Brecht Wyseur and Wil Michiels and Paul Gorissen and Bart Preneel},
    title = {Cryptanalysis of White-Box DES Implementations with Arbitrary External Encodings},
    howpublished = {Cryptology ePrint Archive, Report 2007/104},
    year = {2007},
    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.