Generating Question-Answer Hierarchies Kalpesh Krishna author Mohit Iyyer author 2019-07 text Proceedings of the 57th Annual Meeting of the Association for Computational Linguistics Anna Korhonen editor David Traum editor Lluís Màrquez editor Association for Computational Linguistics Florence, Italy conference publication krishna-iyyer-2019-generating 10.18653/v1/P19-1224 https://aclanthology.org/P19-1224/ 2019-07 2321 2334