Não informado. (1953). Occupational health bulletin. Department of National Health and Welfare, Industrial Health Division.
Chicago-referens (17:e uppl.)Não informado. Occupational Health Bulletin. Ottawa: Department of National Health and Welfare, Industrial Health Division, 1953.
MLA-referens (8:e uppl.)Não informado. Occupational Health Bulletin. Department of National Health and Welfare, Industrial Health Division, 1953.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.