SKOBELEV , V. G. Search on partially ordered structures. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 44, n. 2, p. 253–260, 1992. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/7839. Acesso em: 11 apr. 2025.