Cryptology ePrint Archive: BibTeX Citation of Report 2011/287

@misc{cryptoeprint:2011:287,
    author = {Stanislav Bulygin},
    title = {Algebraic cryptanalysis of the round-reduced and side channel analysis of the full PRINTCipher-48},
    howpublished = {Cryptology ePrint Archive, Report 2011/287},
    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.