Preeda Parkpian และ Apisit Eiumnoh; Lars Reutergardh. (1995) Negative Impacts of Toxic Material Contamination in Soils and Plant Nutrient Balance. <i>Thai Agricultural Research Journal</i>, <i>13</i>(3), 236-239.Preeda Parkpian และ Apisit Eiumnoh; Lars Reutergardh. "Negative Impacts of Toxic Material Contamination in Soils and Plant Nutrient Balance". Thai Agricultural Research Journal 13 (1995):236-239.Preeda Parkpian และ Apisit Eiumnoh; Lars Reutergardh. Negative Impacts of Toxic Material Contamination in Soils and Plant Nutrient Balance. Department of Agriculture:ม.ป.ท. 1995.