2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/129369This paper is a short commentary on the 2005 paper in Nature by S. Rainville et al., which claimed to be ``the most precise direct test of the famous equation", E = mc^2. This communication is directed only to the readers who are familiar with the earlier papers by the author on the subject of mass-energy equivalence.3 pages, no figures. Submitted for publicationGeneral Physicstext