Somboonsuke, Buncha, Prawat Wettayaprasit, Chaiya Kongmanee, Kanokporn Pacheerat, and Benedicte Chambon. 2012. “Rubber Tapping System and Tapping Labor Management of Rubber Farmers’ Households: Comparison among Rubber Ecozones in Songkhla Province”. Kasetsart Journal of Social Sciences 33 (1):92-105. https://so04.tci-thaijo.org/index.php/kjss/article/view/246799.