Kasemsap, S., Hiranrusme, T. and Samsarai, W. (1990) “Cost and Return on Investment of Gerbera Cultivation”, Kasetsart Journal of Social Sciences, 11(1), pp. 32–38. available at: https://so04.tci-thaijo.org/index.php/kjss/article/view/243971 (accessed: 12 September 2026).