Kumar, G. W. W. a. R. Options for developing countries in mining development. Macmillan Press.
Chicago-viite (17. p.)Kumar, Grantley W. Walrond and Raj. Options for Developing Countries in Mining Development. Macmillan Press.
MLA-viite (8. p.)Kumar, Grantley W. Walrond and Raj. Options for Developing Countries in Mining Development. Macmillan Press.
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