Shperberg, Shahaf S., Ariel Felner, Nathan R. Sturtevant, Solomon E. Shimony, and Avi Hayoun. “Enriching Non-Parametric Bidirectional Search Algorithms”. Proceedings of the AAAI Conference on Artificial Intelligence 33, no. 01 (July 17, 2019): 2379-2386. Accessed April 19, 2024. https://ojs.aaai.org/index.php/AAAI/article/view/4078.