1. Resnick D. Degenerative disease of extraspinal locations. In: Diagnosis of bone and joint disorders, vol. 2. 4th ed. Philadelphia: Saunders; 2002. p. 1271–381.
2. Cooper C, Cushnaghan J, Kirwan JR, Dieppe PA, Rogers J, McAlindon T, et al. Radiographic assessment of the knee joint in osteoarthritis. Ann Rheum Dis. 1992;51(1):80–2.
3. Ball J, Jeffrey MR, Kellgren JH. The epidemiology of chronic rheumatism: Atlas of Standard Radiographs of Arthritis. Oxford: Blackwell Scientific Publications; 1963.
4. Özkan K, Baver A, Fatif Ç, Baris Y, Ferhat G, et al. Inter- and intraobserver reliabilities of four different radiographic grading scales of osteoarthritis of the knee joint. J Knee Surg. 2018;31(3):247–53.
5. Gupta KB, Duryea J, Weissman BN. Radiographic evaluation of osteoarthritis. Radiol Clin N Am. 2004;42(1):11–41.