Cryptology ePrint Archive: BibTeX Citation of Report 2001/086

@misc{cryptoeprint:2001:086,
    author = {Helger Lipmaa},
    title = {Statistical Zero-Knowledge Proofs from Diophantine Equations},
    howpublished = {Cryptology ePrint Archive, Report 2001/086},
    year = {2001},
    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.