United Nations Industrial Development Organization. (1972). The manufacture and utilizatin of portland cement. New York: United Nations.
Chicago Style aipamenaUnited Nations Industrial Development Organization. The Manufacture and Utilizatin of Portland Cement. New York: United Nations, 1972.
MLA aipamenaUnited Nations Industrial Development Organization. The Manufacture and Utilizatin of Portland Cement. New York: United Nations, 1972.
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