Das Gupta D K, C. N. C. (1980). Higher productivity in agriculture: Proceedings of the national symposium on approach to higher productivity of crops held at Calcutta. Oxford & IBH publishing company.
Trích dẫn kiểu ChicagoDas Gupta D K, Chattopadhyay N C. Higher Productivity in Agriculture: Proceedings of the National Symposium on Approach to Higher Productivity of Crops Held at Calcutta. Newdelhi: Oxford & IBH publishing company, 1980.
Trích dẫn MLADas Gupta D K, Chattopadhyay N C. Higher Productivity in Agriculture: Proceedings of the National Symposium on Approach to Higher Productivity of Crops Held at Calcutta. Oxford & IBH publishing company, 1980.
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