Karez Namiq Kakarash, Vian Afan Naqshbandi. Comparison between the Effectiveness of McKenzie Extension Exercises and William Flexion Exercises for Treatment of Acute or Sub-acute Low Back Pain. J Popl Ther Clin Pharmacol [Internet]. 2023 Apr. 18 [cited 2024 Jul. 26];30(8):123-3. Available from: https://jptcp.com/index.php/jptcp/article/view/1651