อิงคามระธร ท. (2018) “THE UPGRADING TO SMART FARMER BY LEARNING FROM MASTER SMART FARMER OF PINEAPPLE PLANTATION FARMER IN RATCHABURI PROVINCE”, Phranakhon Rajabhat Research Journal : Humanities and Social Sciences, 14(2), pp. 121–134. available at: https://so05.tci-thaijo.org/index.php/PNRU_JHSS/article/view/131834 (accessed: 29 September 2026).