Iswan, M., Djaingsastro, A. J., & Manurung, S. (2026). Pengaruh Lingkungan terhadap Produktivitas Kelapa Sawit di Afdeling III Kebun Bah Birung Ulu PT Perkebunan Nusantara IV Regional II. Ranah Research : Journal of Multidisciplinary Research and Development, 8(3), 2016-2023. https://doi.org/10.38035/rrj.v8i3.2129