Community Answer Summarization for Multi-Sentence Question with Group L1 Regularization Wen Chan author Xiangdong Zhou author Wei Wang author Tat-Seng Chua author 2012-07 text Proceedings of the 50th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers) Haizhou Li editor Chin-Yew Lin editor Miles Osborne editor Gary Geunbae Lee editor Jong C Park editor Association for Computational Linguistics Jeju Island, Korea conference publication chan-etal-2012-community https://aclanthology.org/P12-1061/ 2012-07 582 591