Cryptology ePrint Archive: BibTeX Citation of Report 2014/708

@misc{cryptoeprint:2014:708,
    author = {Jan Camenisch and Stephan Krenn and Anja Lehmann and Gert Læssøe Mikkelsen and Gregory Neven and Michael Østergaard Pedersen},
    title = {Formal Treatment of Privacy-Enhancing Credential Systems},
    howpublished = {Cryptology ePrint Archive, Report 2014/708},
    year = {2014},
    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.