Não informado. (1921). Sanitation supplements of the tropical diseases bulletin. Bureau of Hygiene and Tropical Diseases.
Chicago-referens (17:e uppl.)Não informado. Sanitation Supplements of the Tropical Diseases Bulletin. London: Bureau of Hygiene and Tropical Diseases, 1921.
MLA-referens (8:e uppl.)Não informado. Sanitation Supplements of the Tropical Diseases Bulletin. Bureau of Hygiene and Tropical Diseases, 1921.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.