JÓNSSON, B. Powers of partially ordered sets: The automorphism group. MATHEMATICA SCANDINAVICA, [S. l.], v. 51, p. 121–141, 1982. DOI: 10.7146/math.scand.a-11967. Disponível em: https://www.mscand.dk/article/view/11967. Acesso em: 5 may. 2024.