2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/179059The paper collects the various pieces of information concerning the relative size of m_u, m_d and m_s. A coherent picture results, which constrains the mass ratios to a rather narrow range: m_u/m_d = 0.553 \pm 0.043, m_s/m_d = 18.9 \pm 0.8.11 pages, 2 figuresHigh Energy Physics - Phenomenologytext