Cryptology ePrint Archive: BibTeX Citation of Report 2004/012

@misc{cryptoeprint:2004:012,
    author = {Maria Isabel Gonzalez Vasco and Rainer Steinwandt },
    title = {Pitfalls in public key cryptosystems based on free partially commutative monoids and groups },
    howpublished = {Cryptology ePrint Archive, Report 2004/012},
    year = {2004},
    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.