Fang, S., Zhao, Y., Tian, W., Lu, J., Zheng, Y., Wang, Y., & Qiu, X. (2026). ORPG: Reconciling Multiple Reward Objectives through Objective-wise Policy Gradients. https://omanscience.com/en/articles/orpg-reconciling-multiple-reward-objectives-through-objective-wise-policy-gradients