2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/137695A phenomenologically successful two-component hadronic duality picture led to Veneziano's amplitude, the fundamental first step to string theory. This picture is briefly recalled and its two components are identified as the open strings (mesons and baryons) and closed strings (Pomeron).added referencesHigh Energy Physics - TheoryHigh Energy Physics - PhenomenologyHistory and Philosophy of Physicstext