KELLGREN, JH. Radiological assessment of osteoarthrosis. Ann Rheum Dis. 1957, 16, 494-501
ALTMAN, R. Development of criteria for the classiification and reporting of osteoarthritis: classification of osteoarthritis. Arthritis Rheum. 1986, 29, 1039-1049
ALTMAN, R. Classification of disease: osteoarthritis. Semin Arthritis Rheum. 1991, 20, 40-47
CUSHNAGHAN, J. Clinical assessment of osteoarthritis of the knee. Ann Rheum Dis. 1990, 49, 768-770
HART, DJ. Clinical signs of early osteoarthritis: reproducibility and relation to X ray changes in 541 women in the general popuration. Ann Rheum Dis. 1991, 50, 467-470