Não informado. (1985). National safety and health news. National Safety Council.
Chicago-Zitierstil (17. Ausg.)Não informado. National Safety and Health News. Chicago, Ill: National Safety Council, 1985.
MLA-Zitierstil (8. Ausg.)Não informado. National Safety and Health News. National Safety Council, 1985.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.