CLAPnq: Cohesive Long-form Answers from Passages in Natural Questions for RAG systems Sara Rosenthal author Avirup Sil author Radu Florian author Salim Roukos author 2025 text journal article Transactions of the Association for Computational Linguistics continuing MIT Press Cambridge, MA periodical academic journal rosenthal-etal-2025-clapnq 10.1162/tacl_a_00729 https://aclanthology.org/2025.tacl-1.3/ 2025 13 53 72