Disability among gainfully occupied persons; an introduction to disability insurance statistics - Falk, I. S. (Isidore Sydney), 1899-1984; Sanders, Barkev Sahak, 1903-; Federman, David, 1913-1944. (Washington, D.C., Federal security agency, Social security board, Bureau of research and statistics, 1945)
"List of references": p. 58-60.