Não informado. (1987). Safety & health. National Safety Council.
Chicagoスタイル(17版)引用形式Não informado. Safety & Health. Chicago, Ill: National Safety Council, 1987.
MLA(8版)引用形式Não informado. Safety & Health. National Safety Council, 1987.
警告: この引用は必ずしも正確ではありません.