2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/185252We demonstrate how heavy mass methods, previously applied to chiral perturbation theory calculations involving the interactions of nucleons and pions, can be generalized to include interactions with the $Δ(1232)$ in a systematic formalism which we call the "small scale expansion."47 page standard latex file with typos correctedHigh Energy Physics - Phenomenologytext