Não informado. (1981). Energy and minerals resources. Business Publishers.
Chicagoスタイル(17版)引用形式Não informado. Energy and Minerals Resources. Silver Spring, Md: Business Publishers, 1981.
MLA(8版)引用形式Não informado. Energy and Minerals Resources. Business Publishers, 1981.
警告: この引用は必ずしも正確ではありません.