Manoch Kongchum และ Wuti Niponkit; R. J. Buresh; D. W. Puckridge. (1999) Soil Nitrate as a Source of Nitrogen for Rainfed and Deep-Flooded Rice. <i>Thai Agricultural Research Journal</i>, <i>17</i>(2), 174-184.Manoch Kongchum และ Wuti Niponkit; R. J. Buresh; D. W. Puckridge. "Soil Nitrate as a Source of Nitrogen for Rainfed and Deep-Flooded Rice". Thai Agricultural Research Journal 17 (1999):174-184.Manoch Kongchum และ Wuti Niponkit; R. J. Buresh; D. W. Puckridge. Soil Nitrate as a Source of Nitrogen for Rainfed and Deep-Flooded Rice. Department of Agriculture:ม.ป.ท. 1999.