2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/163175The theorem on squaring a rectangle from a tiling of a quadrilateral (Schramm and Cannon-Floyd-Parry) gives a combinatorial version of the Riemann mapping theorem. We elucidate by example (the dumbbell) some of the limitations of rectangle-squaring as an approximation to the classical Riemamnn mapping.Complex Variables52C20; 52C26text