Cryptology ePrint Archive: BibTeX Citation of Report 2013/672

@misc{cryptoeprint:2013:672,
    author = {Benjamin Smith},
    title = {Easy scalar decompositions for efficient scalar multiplication on elliptic curves and genus 2 Jacobians},
    howpublished = {Cryptology ePrint Archive, Report 2013/672},
    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.