OpenLoops 2Federico Buccioni, Jean-Nicolas Lang, Jonas M. Lindert, Philipp Maierhöfer, Stefano Pozzorini, Hantian Zhang and Max F. ZollerEur. Phys. J. C, 79 10 (2019) 866DOI: https://doi.org/10.1140/epjc/s10052-019-7306-2