Cryptology ePrint Archive: BibTeX Citation of Report 2010/649

@misc{cryptoeprint:2010:649,
    author = {Douglas Stebila and Lakshmi Kuppusamy and Jothi Rangasamy and Colin Boyd and Juan Gonzalez Nieto},
    title = {Stronger difficulty notions for client puzzles and denial-of-service-resistant protocols},
    howpublished = {Cryptology ePrint Archive, Report 2010/649},
    year = {2010},
    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.