Cryptology ePrint Archive: BibTeX Citation of Report 2015/819

@misc{cryptoeprint:2015:819,
    author = {Jean-Luc Danger and Sylvain Guilley and Philippe Hoogvorst and Cédric Murdica and David Naccache},
    title = {Improving the Big Mac Attack on Elliptic Curve Cryptography},
    howpublished = {Cryptology ePrint Archive, Report 2015/819},
    year = {2015},
    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.