Cryptology ePrint Archive: BibTeX Citation of Report 2011/003

@misc{cryptoeprint:2011:003,
    author = {Daniel J. Bernstein and Tanja Lange and Peter Schwabe},
    title = {On the correct use of the negation map in the Pollard rho method},
    howpublished = {Cryptology ePrint Archive, Report 2011/003},
    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.