Cryptology ePrint Archive: BibTeX Citation of Report 2015/958

@misc{cryptoeprint:2015:958,
    author = {Nilanjan Datta and Avijit Dutta and Mridul Nandi and Goutam Paul and Liting Zhang},
    title = {One-key Double-Sum MAC with Beyond-Birthday Security},
    howpublished = {Cryptology ePrint Archive, Report 2015/958},
    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.