Cryptology ePrint Archive: BibTeX Citation of Report 2013/611

@misc{cryptoeprint:2013:611,
    author = {Mitsugu Iwamoto and Thomas Peyrin and Yu Sasaki},
    title = {Limited-birthday Distinguishers for Hash Functions - Collisions Beyond the Birthday Bound can be Meaningful},
    howpublished = {Cryptology ePrint Archive, Report 2013/611},
    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.