Não informado. (1954). Records of the Geological Survey of Nigeria. Ministry of Mines and Power.
Παραπομπή σε μορφή Chicago (17η εκδ.)Não informado. Records of the Geological Survey of Nigeria. Lagos: Ministry of Mines and Power, 1954.
Παραπομπή σε μορφή MLA (8th εκδ.)Não informado. Records of the Geological Survey of Nigeria. Ministry of Mines and Power, 1954.
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