2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/124034An algebraic deformation theory of module-algebras over a bialgebra is constructed. The cases of module-coalgebras, comodule-algebras, and comodule-coalgebras are also considered.To appear in J. Pure Applied Algebra. 14 pagesRings and AlgebrasAlgebraic TopologyK-Theory and Homology16E40;16W99text