EISENBERG, Murray. A Note on Positively Expansive Endomorphisms. MATHEMATICA SCANDINAVICA, [S. l.], v. 19, p. 217–218, 1966. DOI: 10.7146/math.scand.a-10812. Disponível em: https://tidsskrift.dk/math/article/view/10812. Acesso em: 14 aug. 2026.