Eliartati, E. et al. 2021. Yield Improvement of Upland Rice Planted between Oil Palm Using Organic Matter. Jurnal Lahan Suboptimal : Journal of Suboptimal Lands. 10, 1 (Apr. 2021), 104–112. DOI:https://doi.org/10.36706/JLSO.10.1.2021.532.