Cryptology ePrint Archive: BibTeX Citation of Report 2014/259

@misc{cryptoeprint:2014:259,
    author = {Itai Dinur and Pawel Morawiecki and Josef Pieprzyk and Marian Srebrny and Michal Straus},
    title = {Practical Complexity Cube Attacks on Round-Reduced Keccak Sponge Function},
    howpublished = {Cryptology ePrint Archive, Report 2014/259},
    year = {2014},
    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.