2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/105976We derive the most general lagrangian of the free massive Rarita--Schwinger field, which generalizes the previously known ones. The special role of the reparameterization transformation is discussed.9 pages, revtex4High Energy Physics - TheoryHigh Energy Physics - Phenomenologytext