2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/64872We explain how the computation of induced crossed modules allows the computation of certain homotopy 2-types and, in particular, second homotopy groups. We discuss various issues involved in computing induced crossed modules and give some examples and applications.15 pages, xypic, latex2EAlgebraic TopologyCategory Theory55P10,55Q2,20L05text