BERMAN, Leah Wrenn; CHAPPELL, Glenn; FAUDREE, Jill; GIMBEL, John; HARTMAN, Chris; WILLIAMS, Gordon. Graphs with Obstacle Number Greater than One. Journal of Graph Algorithms and Applications, [S. l.], v. 21, n. 6, p. 1107–1119, 2017. DOI: 10.7155/jgaa.00452. Disponível em: https://jgaa.info/index.php/jgaa/article/view/paper452. Acesso em: 30 jun. 2024.