Event Ontology Completion with Hierarchical Structure Evolution Networks Pengfei Cao author Yupu Hao author Yubo Chen author Kang Liu author Jiexin Xu author Huaijun Li author Xiaojian Jiang author Jun Zhao author 2023-12 text Proceedings of the 2023 Conference on Empirical Methods in Natural Language Processing Houda Bouamor editor Juan Pino editor Kalika Bali editor Association for Computational Linguistics Singapore conference publication cao-etal-2023-event 10.18653/v1/2023.emnlp-main.21 https://aclanthology.org/2023.emnlp-main.21/ 2023-12 306 320