VOROB'EV, N. N.; TSAREV, A. A. On the modularity of a lattice of $τ$-closed $n$-ultiply $ω$-composite formations. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 62, n. 4, p. 453–463, 2010. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/2879. Acesso em: 14 apr. 2025.