Simatupang, Jones, Aditia Erick Cantona Simatupang, dan Manaor Bismar Posman Nababan. “Efisiensi Teknis Perkebunan Kelapa Sawit Rakyat ”. Jurnal Sosial Ekonomi Pertanian 21, no. 1 (Agustus 11, 2025): 131–144. Diakses Maret 22, 2026. https://journal.unhas.ac.id/index.php/jsep/article/view/46205.