STEGEMAN, J. D. On a Theorem of N.Th. Varopoulos. MATHEMATICA SCANDINAVICA, [S. l.], v. 27, p. 50–52, 1970. DOI: 10.7146/math.scand.a-10986. Disponível em: https://www.mscand.dk/article/view/10986. Acesso em: 4 may. 2024.