Cryptology ePrint Archive: BibTeX Citation of Report 2015/725

@misc{cryptoeprint:2015:725,
    author = {Eric Verheul and Sietse Ringers and Jaap-Henk Hoepman},
    title = {The self-blindable U-Prove scheme by Hanzlik and Kluczniak is forgeable},
    howpublished = {Cryptology ePrint Archive, Report 2015/725},
    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.