Song, Yuhang, Jianyi Wang, Thomas Lukasiewicz, Zhenghua Xu, and Mai Xu. “Diversity-Driven Extensible Hierarchical Reinforcement Learning”. Proceedings of the AAAI Conference on Artificial Intelligence 33, no. 01 (July 17, 2019): 4992-4999. Accessed November 30, 2022. https://ojs.aaai.org/index.php/AAAI/article/view/4430.