Koreh, Agabus Ary, Widowati, and Reza Prokoso Dwi Julianto. “Long-Term Residual Effects of Biochar from Tobacco Scraps on Red Spinach (Amaranthus Tricolor) Growth in Entisols: A Five-Year Field Experiment With Urea Fertilizer Addition”. Jurnal Ilmiah Pertanian 20, no. 2 (June 8, 2023): 153-164. Accessed May 18, 2024. https://journal.unilak.ac.id/index.php/jip/article/view/13451.