Cornelsen, Sabine, and Gregor Diatzko. “Planar Confluent Orthogonal Drawings of 4-Modal Digraphs”. Journal of Graph Algorithms and Applications 27, no. 7 (August 1, 2023): 523–540. Accessed December 22, 2024. https://jgaa.info/index.php/jgaa/article/view/paper632.