2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/219348The organization of finite order QCD approximations to $F_2^γ(x,Q^2)$ based on the separation of pure QED contribution from those of genuine QCD nature is discussed.Talk given at the International Symposium PHOTON 2007, Paris, July 2007, 4 pages and 1 figure, references correctedHigh Energy Physics - Phenomenologytext