2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/73231We develop reductions for classifications of singularities of orbit closures in module varieties. Then we show that the orbit closures for representations of Dynkin quivers are regular in codimension two.24 pagesAlgebraic Geometry14B05; 14L30; 16G10; 16G20Orbit closures for representations of Dynkin quivers are regular in codimension twotext