Varina, Firna, Sri Hartoyo, Nunung Kusnadi, and Amzul Rifin. “The Determinants of Technical Efficiency of Oil Palm Smallholders in Indonesia”. International Journal of Economics and Financial Issues 10, no. 6 (November 4, 2020): 89–93. Accessed December 18, 2024. https://mail.econjournals.com/index.php/ijefi/article/view/10594.