APIBANTAWEESAKUL, Sudarat. 2016. “Comparison of Knee Muscle Balance at Different Knee Flexion Angles Between Patients With Patellofemoral Pain Syndrome With Healthy Subjects”. Walailak Journal of Science and Technology (WJST) 14 (8):637-43. https://wjst.wu.ac.th/index.php/wjst/article/view/2523.