Cryptology ePrint Archive: BibTeX Citation of Report 2001/061

@misc{cryptoeprint:2001:061,
    author = {Alexander Kholosha},
    title = {Clock-Controlled Shift Registers for Key-Stream Generation},
    howpublished = {Cryptology ePrint Archive, Report 2001/061},
    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.