Não informado. (1970). Copper abstracts. International Copper Development Council.
Chicagoスタイル(17版)引用形式Não informado. Copper Abstracts. Geneva, Suíça: International Copper Development Council, 1970.
MLA(8版)引用形式Não informado. Copper Abstracts. International Copper Development Council, 1970.
警告: この引用は必ずしも正確ではありません.