KHADZHIIVANOV, N. On $K_{4}^{\prime}$-graphs. Ann. Sofia Univ. Fac. Math. and Inf., [S. l.], v. 87, p. 271–277, 1995. Disponível em: https://ftl5.uni-sofia.bg/index.php/fmi/article/view/420. Acesso em: 21 nov. 2024.