Bagnato, G., Fiorenza, A., Cordova, F., Roberts, W., C, M. , Jr, Greco, D., … Bagnato, G. (1969). Clinical, autoimmune, and psychiatric parameters correlate with sleep disturbance in patients with systemic sclerosis and rheumatoid arthritis. Clinical and Experimental Rheumatology, 34 Suppl 100(5), 49-55. Retrieved from http://www.clinexprheumatol.org/pubmed/find-pii.asp?pii=27192425 (Original work published 1969)