Contrastive Multi-document Question Generation Woon Sang Cho author Yizhe Zhang author Sudha Rao author Asli Celikyilmaz author Chenyan Xiong author Jianfeng Gao author Mengdi Wang author Bill Dolan author 2021-04 text Proceedings of the 16th Conference of the European Chapter of the Association for Computational Linguistics: Main Volume Paola Merlo editor Jorg Tiedemann editor Reut Tsarfaty editor Association for Computational Linguistics Online conference publication cho-etal-2021-contrastive 10.18653/v1/2021.eacl-main.2 https://aclanthology.org/2021.eacl-main.2/ 2021-04 12 30