BRUN, M.; RÖMER, T. On algebras associated to partially ordered sets. MATHEMATICA SCANDINAVICA, [S. l.], v. 103, n. 2, p. 169–185, 2008. DOI: 10.7146/math.scand.a-15076. Disponível em: https://www.mscand.dk/article/view/15076. Acesso em: 29 apr. 2024.