KAUFMANN, Michael; PACH, János; TÓTH, Géza; UECKERDT, Torsten. The number of crossings in multigraphs with no empty lens. Journal of Graph Algorithms and Applications, [S. l.], v. 25, n. 1, p. 383–396, 2021. DOI: 10.7155/jgaa.00563. Disponível em: https://jgaa.info/index.php/jgaa/article/view/paper563. Acesso em: 30 jun. 2024.