2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/124197Let $H$ be a character Hopf algebra. Every right coideal subalgebra that contains the coradical has a PBW-basis which can be extended up to a PBW-basis of $H.$Quantum AlgebraRings and Algebras16W30; 17B37text