Williams, J. F. (1930). Hygiene and sanitation: The essentials of modern health care (2nd ed., rev.). W.B. Saunders company.
Dyfyniad Arddull ChicagoWilliams, Jesse Feiring. Hygiene and Sanitation: The Essentials of Modern Health Care. 2nd ed., rev. Philadelphia ; London: W.B. Saunders company, 1930.
Dyfyniad MLAWilliams, Jesse Feiring. Hygiene and Sanitation: The Essentials of Modern Health Care. 2nd ed., rev. W.B. Saunders company, 1930.
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