From Top-1 to Top-K: A Reproducibility Study and Benchmarking of Counterfactual Explanations for Recommender Systems. - Quang-Huy Nguyen; Thanh-Hai Nguyen; Khac-Manh Thai; Duc-Hoang Pham; Huy-Son Nguyen; Cam-Van Thi Nguyen; Masoud Mansoury; Duc-Trong Le; Hoang-Quynh Le (CoRR, 2026)