Wang, R., H. Wei, B. An, Z. Feng, and J. Yao. “Commission Fee Is Not Enough: A Hierarchical Reinforced Framework for Portfolio Management”. Proceedings of the AAAI Conference on Artificial Intelligence, vol. 35, no. 1, May 2021, pp. 626-33, https://ojs.aaai.org/index.php/AAAI/article/view/16142.