Simultaneous Selection and Adaptation of Source Data via Four-Level Optimization Pengtao Xie author Xingchen Zhao author Xuehai He author 2024 text journal article Transactions of the Association for Computational Linguistics continuing MIT Press Cambridge, MA periodical academic journal xie-etal-2024-simultaneous 10.1162/tacl_a_00658 https://aclanthology.org/2024.tacl-1.25/ 2024 12 449 466