Lukjan, A., A. Iyaruk, and C. Petchprakob. “Soil Water Retention Curve and Permeability Function of the Para Rubber Biopolymer Treated Sand”. Interdisciplinary Research Review, vol. 15, no. 5, Oct. 2020, pp. 1-7, https://ph02.tci-thaijo.org/index.php/jtir/article/view/241025.