Cryptology ePrint Archive: BibTeX Citation of Report 2011/484

@misc{cryptoeprint:2011:484,
    author = {Johannes Buchmann, Erik Dahmen, and Andreas Hülsing},
    title = {XMSS - A Practical Forward Secure Signature Scheme based on Minimal Security Assumptions},
    howpublished = {Cryptology ePrint Archive, Report 2011/484},
    year = {2011},
    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.