GILMER, R.; HEINZER, W. An Application of Jonsson Modules to Some Questions Concerning Proper Subrings. MATHEMATICA SCANDINAVICA, [S. l.], v. 70, p. 34–42, 1992. DOI: 10.7146/math.scand.a-12385. Disponível em: https://tidsskrift.dk/math/article/view/12385. Acesso em: 13 aug. 2026.