KRISTENSEN, Leif; MADSEN, Ib. Note on Whitehead Products in Spheres. Mathematica Scandinavica, Berkeley, CA, United States, v. 21, p. 301–314, 1967. DOI: 10.7146/math.scand.a-10865. Disponível em: https://journals.msp.org/mscand/article/view/2460. Acesso em: 25 jul. 2026.