Cryptology ePrint Archive: BibTeX Citation of Report 2015/234

@misc{cryptoeprint:2015:234,
    author = {Megha Agrawal and Donghoon Chang and Mohona Ghosh and Somitra Kumar Sanadhya},
    title = {Collision Attack on 4-branch, Type-2 GFN based Hash Functions using Sliced Biclique Cryptanalysis Technique},
    howpublished = {Cryptology ePrint Archive, Report 2015/234},
    year = {2015},
    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.