Fajarindo, F., Suwardi, Iskandar, Limin, A., & Dewi, S. K. (2026). Amelioration of Ultisol Acidity Using Coal Ash and Lignite-Enriched Compost. Acta Solum, 4(2), 94–99. https://doi.org/10.20527/actasolum.v4i2.3614