Slavchev, Svetoslav. “Translation and Validation of the Bulgarian Version of the Knee Injury and Osteoarthritis Outcome Score (KOOS) in Patients With Osteoarthritis”. Proceedings of the Bulgarian Academy of Sciences 76, no. 3 (March 27, 2023): 457–463. Accessed March 20, 2025. https://www.proceedings.bas.bg/index.php/cr/article/view/280.