2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/185297Two program packages are presented for evaluating one-loop amplitudes. They can work either in dimensional regularization or in constrained differential renormalization. The latter method is found at the one-loop level to be equivalent to regularization by dimensional reduction.16 pages, uses amstex and axodraw, 1 eps figureHigh Energy Physics - Phenomenologytext