LORING, T. A. When matrices commute. MATHEMATICA SCANDINAVICA, [S. l.], v. 82, n. 2, p. 305–319, 1998. DOI: 10.7146/math.scand.a-13839. Disponível em: https://www.mscand.dk/article/view/13839. Acesso em: 4 may. 2024.