Rockville, Md. : U.S. Department of Health, Education, and Welfare, Public Health Service, Health Services and Mental Health Administration, National Center for Health Statistics, 1973
"Statistics on volume of medical and dental x-ray visits, by area of body x-rayed, place of x-ray visit, type of x-ray, age, sex, race, place of residence, geographic region, family income, and education. Based on data collected in household interviews during the period April-September 1970."