Cryptology ePrint Archive: BibTeX Citation of Report 2015/313

@misc{cryptoeprint:2015:313,
    author = {Ronald Cramer and Léo Ducas and Chris Peikert and Oded Regev},
    title = {Recovering Short Generators of Principal Ideals in Cyclotomic Rings},
    howpublished = {Cryptology ePrint Archive, Report 2015/313},
    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.