Cryptology ePrint Archive: BibTeX Citation of Report 2009/049

@misc{cryptoeprint:2009:049,
    author = {Aileen Zhang, Chu-Wee Lim, Khoongming Khoo, Wei Lei and Josef Pieprzyk },
    title = {Extensions of the Cube Attack based on Low Degree Annihilators},
    howpublished = {Cryptology ePrint Archive, Report 2009/049},
    year = {2009},
    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.