BAAS, N. A. On Formal Groups and Singularities in Complex Corbordism Theory. MATHEMATICA SCANDINAVICA, [S. l.], v. 33, p. 303–313, 1973. DOI: 10.7146/math.scand.a-11492. Disponível em: https://www.mscand.dk/article/view/11492. Acesso em: 27 apr. 2024.