Phitthayaphinant, Purawich, and Buncha Somboonsuke. 2013. “Purchasing Decision Probability on Health Products Made from Cold-Pressed Palm Oil in Hat Yai District, Songkhla Province”. Kasetsart Journal of Social Sciences 34 (3):413-27. https://so04.tci-thaijo.org/index.php/kjss/article/view/247089.