Xiao, Y., C. Tan, Z. Fan, Q. Xu, and W. Zhu. “Joint Entity and Relation Extraction With a Hybrid Transformer and Reinforcement Learning Based Model”. Proceedings of the AAAI Conference on Artificial Intelligence, vol. 34, no. 05, Apr. 2020, pp. 9314-21, doi:10.1609/aaai.v34i05.6471.