Nattaporn Prakongkep, Anchalee Suddhiprakarn, Irb Kheoruenromne, and R.J. Gilkes. “Micromorphological Properties of Thai Paddy Soils”. Agriculture and Natural Resources, vol. 41, no. 5, Dec. 2007, pp. 42-48, https://li01.tci-thaijo.org/index.php/anres/article/view/244334.