Cryptology ePrint Archive: BibTeX Citation of Report 2007/048

@misc{cryptoeprint:2007:048,
    author = {Daniel R. L. Brown and Kristian Gj{\o}steen},
    title = {A Security Analysis of the NIST SP 800-90 Elliptic Curve Random Number Generator},
    howpublished = {Cryptology ePrint Archive, Report 2007/048},
    year = {2007},
    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.