Não informado. (1964). Coal, gold and base minerals of Southern Africa. Pithead Press.
Chicago-viite (17. p.)Não informado. Coal, Gold and Base Minerals of Southern Africa. Johannesburg, Africa do Sul: Pithead Press, 1964.
MLA-viite (8. p.)Não informado. Coal, Gold and Base Minerals of Southern Africa. Pithead Press, 1964.
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