\begin{aligned} & \text { A } \mathbb{Z} \text {-BASIS OF THE } S_n \text {-INVARIANT SUBRING } \\ & \text { OF } \mathbb{Z}\left[a_i-a_j\right] \end{aligned}. JP Journal of Algebra, Number Theory and Applications, [S. l.], v. 64, n. 3, p. 251–287, 2025. DOI: 10.17654/0972555525015. Disponível em: https://pphmjopenaccess.com/jpjana/article/view/2973. Acesso em: 5 jan. 2026.