Não informado. (1968). Abstracts on hygiene. Bureau of Hygiene and Tropical Diseases.
Chicago-referens (17:e uppl.)Não informado. Abstracts on Hygiene. London: Bureau of Hygiene and Tropical Diseases, 1968.
MLA-referens (8:e uppl.)Não informado. Abstracts on Hygiene. Bureau of Hygiene and Tropical Diseases, 1968.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.