Não informado. (1946). Mining Survey. Transvaal and Orange Free State Chamber of Mines.
Style de citation Chicago (17e éd.)Não informado. Mining Survey. Johannesburg, Africa do Sul: Transvaal and Orange Free State Chamber of Mines, 1946.
Style de citation MLA (8e éd.)Não informado. Mining Survey. Transvaal and Orange Free State Chamber of Mines, 1946.
Attention : ces citations peuvent ne pas être correctes à 100%.