Não informado. (1970). Copper Abstracts. Copper Development Association.
Style de citation Chicago (17e éd.)Não informado. Copper Abstracts. London: Copper Development Association, 1970.
Style de citation MLA (8e éd.)Não informado. Copper Abstracts. Copper Development Association, 1970.
Attention : ces citations peuvent ne pas être correctes à 100%.