2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/179657We study the value of the light quark masses combination $m_u+m_d$ in QCD using both Finite Energy Sum Rules and Laplace Sum Rules. We have performed a detailed analysis of both the perturbative QCD and the hadronic parametrization inputs needed in these Sum Rules. As main result, we obtain $m_u\left(1~{\rm GeV}^2\right) + m_d \left(1~{\rm GeV}^2\right) = \left(12\pm2.5\right)~{\rm MeV}$ for the running $\overline{MS}$ masses.17 pages, LaTeX, 5 postscript figures included, uses cite.sty(included) and epsf.styHigh Energy Physics - Phenomenologytext