qayum, a. (1964). cumulative marginal productivity life of plants and the optimal technology. the institute of national planning.
Chicago-viite (17. p.)qayum, a. Cumulative Marginal Productivity Life of Plants and the Optimal Technology. cairo: the institute of national planning, 1964.
MLA-viite (9. p.)qayum, a. Cumulative Marginal Productivity Life of Plants and the Optimal Technology. the institute of national planning, 1964.
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