SINGER, M. A Product Theorem for Lattices over Orders. MATHEMATICA SCANDINAVICA, [S. l.], v. 29, p. 50–54, 1971. DOI: 10.7146/math.scand.a-11033. Disponível em: https://www.mscand.dk/article/view/11033. Acesso em: 2 may. 2024.