2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/224895We study a system of pseudodifferential equations that is elliptic in the sense of Petrovskii on a closed compact smooth manifold. We prove that the operator generated by the system is Fredholm one on a refined two-sided scale of the functional Hilbert spaces. Elements of this scale are the special isotropic spaces of Hörmander--Volevich--Paneah.Analysis of PDEs35J45, 46E35Elliptic systems of pseudodifferential equations in a refined scale on a closed manifoldtext