Cryptology ePrint Archive: BibTeX Citation of Report 2013/322

@misc{cryptoeprint:2013:322,
    author = {Jean-Philippe Aumasson and Samuel Neves and Zooko Wilcox-O'Hearn and Christian Winnerlein},
    title = {BLAKE2: simpler, smaller, fast as MD5},
    howpublished = {Cryptology ePrint Archive, Report 2013/322},
    year = {2013},
    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.