1. Psoriatic arthritis: epidemiology, clinical features, course, and outcome;Gladman;Ann Rheum Dis,2005
2. Psoriatic arthritis;Boumpas,2001
3. Prospective analysis of psoriatic arthritis in patients hospitalized for psoriasis;Leonard;Mayo Clin Proc,1978
4. The epidemiology of psoriatic arthritis in Olmsted County, Minnesota, USA, 1982-1991;Shbeeb;J Rheumatol,2000
5. Burden of disease: psoriasis and psoriatic arthritis;Boehncke;Am J Clin Dermatol,2013