Ninja implements the Laurent series expansion method for the computation of one-loop integrals.

It is based on: * P. Mastrolia, E. Mirabella and T. Peraro, "Integrand reduction of one-loop scattering amplitudes through Laurent series expansion," JHEP 1206 (2012) 095 arXiv:1203.0291 [hep-ph] DOI: 10.1007/JHEP06(2012)095 * T. Peraro, "Ninja: Automated Integrand Reduction via Laurent Expansion for One-Loop Amplitudes," Comput. Phys. Commun. 185 (2014) 2771 arXiv:1403.1229 [hep-ph] DOI: 10.1016/j.cpc.2014.06.017