Douglas, J. S. (1977). Hydroponics of Bengal system with notes on other methods of soilless cultivation (5.). Oxford University Press.
Trích dẫn kiểu ChicagoDouglas, J S. Hydroponics of Bengal System with Notes on Other Methods of Soilless Cultivation. 5. London: Oxford University Press, 1977.
Trích dẫn MLADouglas, J S. Hydroponics of Bengal System with Notes on Other Methods of Soilless Cultivation. 5. Oxford University Press, 1977.
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