Não informado. (1962). Annals of the Geological Survey. Republic of South Africa, Department of Mines.
Chicago Style (17. basım) AtıfNão informado. Annals of the Geological Survey. Pretoria, Africa do Sul: Republic of South Africa, Department of Mines, 1962.
MLA (8th ed.) AtıfNão informado. Annals of the Geological Survey. Republic of South Africa, Department of Mines, 1962.
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