2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/192426We consider the problem of determining amplitudes from observables for the case of pseudoscalar meson photoproduction. We find a number of surprisingly simple constraints which give necessary conditions for a complete set of measurements. These results contradict one of the selection rules derived previously.7 pagesNuclear Theorytext