2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/78957It is shown, under the assumption of Jensen's principle $\lozenge$, that if for a complex L with $[L] \geq [S^{4}]$ there exists a metrizable compactum whose extension dimension is L, then there exists a differentiable, countably compact, perfectly normal and hereditarily separable 4-manifold whose extension dimension is also [L].13 pagesGeneral Topology54F45; 57N99text