2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/158234Let $KG$ be the group ring of a group $G$ over a commutative ring $K$ with unity. The rings $KG$ are described for which $xx^σ=x^σx$ for all $x=\sum_{g\in G}α_gg\in KG$, where \quad $x\mapsto x^σ=~\sum_{g\in G}α_gf(g)σ(g)$\quad is an involution of $KG$; here $f: G\to U(K)$ is a homomorphism and $σ$ is an anti-automorphism of order two of $G$.8 pagesRings and AlgebrasGroup Theory16S34text