Effect of an Oral Preparation Containing Hyaluronic Acid, Chondroitin Sulfate, Hydrolyzed Collagen Type II and Hydrolyzed Keratin on Synovial Fluid Features and Clinical Indices in Knee Osteoarthritis. A Pilot Study. Reumatismo 2020, 72 (3), 125-130. https://doi.org/10.4081/reumatismo.2020.1272.