2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/197168We argue that the large-Nc expansion of QCD can be used to treat a Lagrangian of resonances in a perturbative way. As an illustration of this we compute the L_10 coupling of the Chiral Lagrangian by integrating out resonance fields at one loop. Given a Lagrangian and a renormalization scheme, this is how in principle one can answer in a concrete and unambiguous manner questions such as at what scale resonance saturation takes place.9 pages, 5 figures. Enlarged discussion, results unchanged. To be published in Phys. Rev. DHigh Energy Physics - PhenomenologyNuclear Theorytext