Não informado. (1957). Bibliography and Subject Index of South African Geology. Geological Survey of South Africa.
Chicago-referens (17:e uppl.)Não informado. Bibliography and Subject Index of South African Geology. Pretoria, Africa do Sul: Geological Survey of South Africa, 1957.
MLA-referens (8:e uppl.)Não informado. Bibliography and Subject Index of South African Geology. Geological Survey of South Africa, 1957.
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