PICAVET, Gabriel. Ultrafiltres sur un espace spectral - Anneaux de Baer - Anneaux a spectre minimal compact. Mathematica Scandinavica, Berkeley, CA, United States, v. 46, p. 23–53, 1980. DOI: 10.7146/math.scand.a-11849. Disponível em: https://journals.msp.org/mscand/article/view/1798. Acesso em: 25 jul. 2026.