• For an approach that uses a pure curiosity-driven approach in the Atari games, read the paper Large-scale study of curiosity-driven learning (https://arxiv.org/pdf/1808.04355.pdf).
• For practical use of domain randomization for learning dexterous in-hand manipulation, read the paper Learning Dexterous In-Hand Manipulation (https://arxiv.org/pdf/1808.00177.pdf).
• For some work that shows how human feedback can be applied as an alternative to the reward function, read the paper Deep Reinforcement Learning from Policy-Dependent Human Feedback (https://arxiv.org/pdf/1902.04257.pdf).