2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/195073We calculate contributions of hadron resonances to two-photon exchange effects in electron-proton scattering. In addition to the nucleon and P33 resonance, the following heavier resonances are included as intermediate states in the two-photon exchange diagrams: D13, D33, P11, S11 and S31. We show that the corrections due to the heavier resonances are smaller that the dominant nucleon and P33 contributions. We also find that there is a partial cancellation between the contributions from the spin 1/2 and spin 3/2 resonances, which results in a further suppression of their aggregate two-photon exchange effect.6 pages, 1 figure; additional comparison with data, results unchanged; to be published in Phys. Rev. CNuclear Theorytext