1. Classification of progressive systemic sclerosis (scleroderma);Giordano,1985
2. Scleroderma (systemic sclerosis): classification, subsets, and pathogenesis;LeRoy;J Rheumatol,1988
3. Preliminary criteria for the classification of systemic sclerosis (scleroderma);Arthritis Rheum,1980
4. Predictors of survival in systemic sclerosis (scleroderma);Altman;Arthritis Rheum,1991
5. Epidemiology of systemic sclerosis (scleroderma);Medsger;Ann Intern Med,1971