BAVULA, V. V. Extreme modules over the Weyl algebra $A_n$. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 45, n. 9, p. 1187–1197, 1993. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/5920. Acesso em: 5 dec. 2025.