@inproceedings{ni-etal-2019-learning, title = "Learning to Attend On Essential Terms: An Enhanced Retriever-Reader Model for Open-domain Question Answering", author = "Ni, Jianmo and Zhu, Chenguang and Chen, Weizhu and McAuley, Julian", editor = "Burstein, Jill and Doran, Christy and Solorio, Thamar", booktitle = "Proceedings of the 2019 Conference of the North {A}merican Chapter of the Association for Computational Linguistics: Human Language Technologies, Volume 1 (Long and Short Papers)", month = jun, year = "2019", address = "Minneapolis, Minnesota", publisher = "Association for Computational Linguistics", url = "https://aclanthology.org/N19-1030/", doi = "10.18653/v1/N19-1030", pages = "335--344" }