Não informado. (1987). Safety and health at work. International Occupational Safety and Health Information Centre.
Chicago-referens (17:e uppl.)Não informado. Safety and Health at Work. Geneva, Suíça: International Occupational Safety and Health Information Centre, 1987.
MLA-referens (8:e uppl.)Não informado. Safety and Health at Work. International Occupational Safety and Health Information Centre, 1987.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.