Naritoom, C., K. Simsiriwong, J.-C. Castella, G. Trebuil, P. Saritniran, and J. Jantrprasert. “On-Farm Diagnosis on the Intensification of Vegetable Cropping System for Exports to Improve the Sustainability of Small-Scale Farming Systems in Kamphaengsaen Area”. Kasetsart Journal of Social Sciences, vol. 12, no. 2, July 1991, pp. 118-27, https://so04.tci-thaijo.org/index.php/kjss/article/view/244001.