Liu, T. (1991). Effecient use of nitrogen in crop production. Food & Fertilizer Technology Center.
Chicago-viite (17. p.)Liu, Ta-chiang. Effecient Use of Nitrogen in Crop Production. Taipei City: Food & Fertilizer Technology Center, 1991.
MLA-viite (9. p.)Liu, Ta-chiang. Effecient Use of Nitrogen in Crop Production. Food & Fertilizer Technology Center, 1991.
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