Não informado. (1970). Smoking and health bulletin. U.S. National Clearinghouse for Smoking and Health.
Chicago-referens (17:e uppl.)Não informado. Smoking and Health Bulletin. Arlington, Va: U.S. National Clearinghouse for Smoking and Health, 1970.
MLA-referens (8:e uppl.)Não informado. Smoking and Health Bulletin. U.S. National Clearinghouse for Smoking and Health, 1970.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.