HINKKANEN, A.; MARTIN, G. J. Abelian nondiscrete convergence groups in the plane . Annales Fennici Mathematici, [S. l.], v. 19, n. 2, p. 205–246, 1994. Disponível em: https://afm.journal.fi/article/view/134805. Acesso em: 25 nov. 2024.