Cryptology ePrint Archive: BibTeX Citation of Report 2014/871

@misc{cryptoeprint:2014:871,
    author = {Anton A. Kuznetsov},
    title = {An algorithm for MD5 single-block collision attack using high-performance computing cluster},
    howpublished = {Cryptology ePrint Archive, Report 2014/871},
    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.