2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/156390This is an expository account of the following result: we can construct a group by means of twisted Z_2-graded vectorial bundles which is isomorphic to K-theory twisted by any degree three integral cohomology class.10 pages, LaTeX 2e; main statement improved, sketch of proof addedK-Theory and HomologyAlgebraic Topologytext