Diphoton decay of the higgs from the Epstein–Glaser viewpoint Paweł Duch, Michael Dütsch and José M. Gracia-Bondía Eur. Phys. J. C, 81 2 (2021) 131 Published online: 06 February 2021 DOI: 10.1140/epjc/s10052-021-08898-z