Free Indexation: Combinatorial Analysis and A Compositional Algorithm Sandiway Fong author 1990-06 text 28th Annual Meeting of the Association for Computational Linguistics Association for Computational Linguistics Pittsburgh, Pennsylvania, USA conference publication fong-1990-free 10.3115/981823.981837 https://aclanthology.org/P90-1014/ 1990-06 105 110