Não informado. (1976). Occupational Health and Safety. Stevens Publishing.
Chicago-referens (17:e uppl.)Não informado. Occupational Health and Safety. Waco, Tex: Stevens Publishing, 1976.
MLA-referens (8:e uppl.)Não informado. Occupational Health and Safety. Stevens Publishing, 1976.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.