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2. 2. American Medical Association, Bureau of Medical Economic Research . Handbook of sickness insurance, state medicine and cost of medical care . Chicago, American Medical Association, 1939 . 182 p. (p. 182 ).
3. 3. O. W. Anderson, Family medical costs and voluntary health insurance . New York, McGraw-Hill, 1956 . XIX + 251 p. (p. XIX + 251 ).
4. Family dental costs and other personal health services: a nationwide survey
5. 5. O. W. Anderson, Patricia Collette, and J. J. Feldman, Family expenditure patterns for personal health services, 1953 and 1958; nationwide surveys . (Research Series No. 14), New York, Health Information Foundation, 1960 . 68 p. (p. 68 , 68 , 68 ) (Tables 8, 13, 22).