“Provision of Urea Fertilizer and Organic Fertilizer of Rice Husk Charcoal on the Growth of Oil Palm Seeds”. Jurnal Online Pertanian Tropik 9, no. 2 (September 8, 2022): 170–174. Accessed February 4, 2026. https://idjpcr.usu.ac.id/jpt/article/view/9534.