"Wirtschaftszeitschrift." . . "Mijnbouwindustrie." . . "Südafrika." . . "Bedrijfseconomie." . . "Anglo-American Plc (London)" . . . . . . . . . . . . "Bergbau. Industrie. Mineralien. Johannesburg." . . . . . . . . "\"A review published in the interests of mining, industrial, scientific and economic progress\" (varies slightly)."@en . "\"A review published in the interests of mining, industrial, scientific and economic progress\" (varies slightly)." . "Quarterly review published in the interests of mining, industrial, scientific and economic progress" . . . . . "Periodicals"@en . . "Periodicals" . . "Optima"@es . "Optima"@en . "Optima" . . "Tijdschrift" . . "Optima (Johannesburg, South Africa)"@en . "Optima : a quarterly review published in the interests of mining, industrial, scientific and economic progress"@en . . . . . . . . . . . . . . . . . . . . "Africa, Southern Industries Periodicals." . . "Economics." . . "Chemische technologie." . . "Mining." . . "MINING INDUSTRY." . . "Minerals." . . "SOUTH AFRICA." . . "Anglo-American Corporation of South Africa." . . "INDUSTRY." . .