Argan, P., Audit, G., Bloch, A., de Botton, N., Faure, J.-L., Schuhl, C., Tamas, G., Tzara, C., Vincent, E., Van Oystaeyen, B., Deutsch, J., Favart, D., & Prieels, R. (1980). pi0 photoproduction near threshold on hydrogen, deuterium, He-3, and He-4. Physical Review C, Nuclear Physics, 21, 1416-1425. https://doi.org/10.1103/PhysRevC.21.1416 (Original work published 1980)