Keyder, Emil, Joerg Hoffmann, and Patrik Haslum. “Semi-Relaxed Plan Heuristics”. Proceedings of the International Conference on Automated Planning and Scheduling 22, no. 1 (May 14, 2012): 128-136. Accessed November 8, 2024. https://ojs.aaai.org/index.php/ICAPS/article/view/13496.