FIFE, James H. Triple products in the Steenrod algebra. Mathematica Scandinavica, Berkeley, CA, United States, v. 55, p. 201–215, 1984. DOI: 10.7146/math.scand.a-12076. Disponível em: https://journals.msp.org/mscand/article/view/1596. Acesso em: 25 jul. 2026.