Não informado. (2004). SA mining: South African mining, coal, gold, and base minerals. Johnnic Publishing.
Chicago-viite (17. p.)Não informado. SA Mining: South African Mining, Coal, Gold, and Base Minerals. Pinegowrie, Africa do Sul: Johnnic Publishing, 2004.
MLA-viite (8. p.)Não informado. SA Mining: South African Mining, Coal, Gold, and Base Minerals. Johnnic Publishing, 2004.
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