Cryptology ePrint Archive: BibTeX Citation of Report 2015/534

@misc{cryptoeprint:2015:534,
    author = {Sergey Agievich and Anastasiya Gorodilova and Nikolay Kolomeec and Svetla Nikova and Bart Preneel and Vincent Rijmen and George Shushuev and Natalia Tokareva and Valeria Vitkup},
    title = {Problems, solutions and experience of the first international student's Olympiad in cryptography},
    howpublished = {Cryptology ePrint Archive, Report 2015/534},
    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.