2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/70044We describe all proper holomorphic mappings of the symmetrized polydisc and study its geometric properties. We also apply the obtained results to the study of the spectral unit ball in $\MM_n(\CC^n)$.9 pagesComplex Variables32H35, 32A25text