Songsiengchai, Patchaya, Shaufique F. Sidique, Marcel Djama, and W.N.W. Azman-Saini. 2018. “Asymmetric adjustments in the Thai palm oil market”. Kasetsart Journal of Social Sciences 41 (1):220–225. https://so04.tci-thaijo.org/index.php/kjss/article/view/231630.