“Lignite-Based Organic Fertilizer Improves Soil Quality and Yield of Rice in Belitang South Sumatera”. JOURNAL OF TROPICAL SOILS 24, no. 3 (September 18, 2019): 109–117. Accessed January 3, 2026. https://journal.unila.ac.id/index.php/tropicalsoil/article/view/397.