Li X, Wang B, Yang X, Luo M. Self-Improving Sparse Retrieval Through Heuristic Representation Refinement and Representation-Focused Learning. AAAI [Internet]. 2026 Mar. 14 [cited 2026 May 15];40(18):15135-43. Available from: https://ojs.aaai.org/index.php/AAAI/article/view/38537