Cryptology ePrint Archive: BibTeX Citation of Report 2013/504

@misc{cryptoeprint:2013:504,
    author = {Reza Azarderakhsh and Koray Karabina},
    title = {A Comparison of Double Point Multiplication Algorithms and their Implementation over Binary Elliptic Curves},
    howpublished = {Cryptology ePrint Archive, Report 2013/504},
    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.