DELEANU, A.; HILTON, P. J. Some Remarks on General Cohomology Theories. Mathematica Scandinavica, Berkeley, CA, United States, v. 22, p. 227–240, 1968. DOI: 10.7146/math.scand.a-10887. Disponível em: https://journals.msp.org/mscand/article/view/2412. Acesso em: 25 jul. 2026.