2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/214800We derive a compact Yennie gauge representation for the off-shell one-loop electron-photon vertex, and discuss it properties. This expression is explicitly infrared finite, and it has proved to be extremely useful in multiloop calculations in the QED bound state problem.Revtex, 12 pp., 1 fig., one reference added. Two misprints in intermediate formulae correctedHigh Energy Physics - Phenomenologytext