2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/214589The Monte Carlo event generator PHOKHARA, which simulates hadron and muon production at electron-positron colliders through radiative return, has been extended to final states with three pions. A model for the form factor based on generalized vector dominance has been employed, which is consistent with presently available experimental observations.8 pages, 8 figures. Final version to appear in Eur. Phys. J. CHigh Energy Physics - Phenomenologytext