Augmenting Transformers with KNN-Based Composite Memory for Dialog Angela Fan author Claire Gardent author Chloé Braud author Antoine Bordes author 2021 text journal article Transactions of the Association for Computational Linguistics continuing MIT Press Cambridge, MA periodical academic journal fan-etal-2021-augmenting 10.1162/tacl_a_00356 https://aclanthology.org/2021.tacl-1.6/ 2021 9 82 99