1.
Purba B, Gultom R, Feby Y, Sihombing T. Economic Valuation of Natural Resources of Oil Palm Plantations in Mandailing Natal. ijeit [Internet]. 30Aug.2023 [cited 5May2026];6(3):459-66. Available from: https://jurnal.peneliti.net/index.php/IJEIT/article/view/7021