References ========== Zhi-Hua Zhou. `Abductive learning: Towards bridging machine learning and logical reasoning. `_. **Science China Information Sciences**, 2019, 62: 076101. Zhi-Hua Zhou and Yu-Xuan Huang. `Abductive learning `_. In P. Hitzler and M. K. Sarker eds., **Neuro-Symbolic Artificial Intelligence: The State of the Art**, IOP Press, Amsterdam, 2022, p.353-379