Tsiaras, Vassilis, and Ioannis Tollis. “DAGmaps and ε-Visibility Representations for DAGs: Algorithms and Characterizations”. Journal of Graph Algorithms and Applications 16, no. 2 (January 1, 2012): 359–380. Accessed June 19, 2025. https://jgaa-v4.cs.brown.edu/index.php/jgaa/article/view/paper262.