KLAWITTER, Jonathan; ZINK, Johannes. Upward Planar Drawings with Three and More Slopes. Journal of Graph Algorithms and Applications, [S. l.], v. 27, n. 2, p. 49–70, 2023. DOI: 10.7155/jgaa.00617. Disponível em: https://jgaa-v4.cs.brown.edu/index.php/jgaa/article/view/paper617. Acesso em: 6 may. 2025.