2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/152365The known correspondence between the Kronig-Penney model and certain Jacobi matrices is extended to a wide class of Schroedinger operators on graphs. Examples include rectangular lattices with and without a magnetic field, or comb-shaped graphs leading to a Maryland-type model.LaTeX, 11 pages, no figuresFunctional AnalysisOperator AlgebrasQuantum Physicstext