GULLIKSEN, T. H. A Note on the Homology of Local Rings. Mathematica Scandinavica, Berkeley, CA, United States, v. 21, p. 296–300, 1967. DOI: 10.7146/math.scand.a-10864. Disponível em: https://journals.msp.org/mscand/article/view/2461. Acesso em: 25 jul. 2026.