Fernandez-Merchant, Silvia, and Rimma Hamalainen. “Direction-Critical Configurations in Noncentral General Position: Discrete and Computational Geometry, Graphs, and Games”. Thai Journal of Mathematics 21, no. 4 (December 31, 2023): 937–956. Accessed May 9, 2024. https://thaijmath2.in.cmu.ac.th/index.php/thaijmath/article/view/1557.