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. (1979). Measurement of Photoproduction of pi+ Near Threshold on He-3. Physical Review C, Nuclear Physics, 20, 242-247. https://doi.org/10.1103/PhysRevC.20.242 (Original work published 1979)