Ramazzina, Ileana, Francesco Pogliacomi, Silvia Bertuletti, and Cosimo Costantino. 2016. “Long Term Effect of Selective Muscle Strengthening in Athletes With Patellofemoral Pain Syndrome”. Acta Biomedica Atenei Parmensis 87 (1 -S): 60-68. https://mattioli1885journals.com/index.php/actabiomedica/article/view/5351.