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Selwyn D. Collins, F. Ruth Phillips, Dorothy S. Oliver, Specific Causes of Illness Found in Monthly Canvasses of Families: Sample of the Eastern Health District of Baltimore, 1938-43, Public Health Reports (1896-1970), Vol. 65, No. 39 (Sep. 29, 1950), pp. 1235-1264
Collins et al. (Sun,) studied this question.