G. Kobayashi, T. Kuribayashi, S. Yokoi, and K. Inui. Proceedings of the 2020 Conference on Empirical Methods in Natural Language Processing (EMNLP), page 7057--7075. Online, Association for Computational Linguistics, (November 2020)
S. Jain, and B. Wallace. Proceedings of the 2019 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies, NAACL-HLT 2019, Minneapolis, MN, USA, June 2-7, 2019, Volume 1 (Long and Short Papers), page 3543--3556. Association for Computational Linguistics, (2019)