Purnomo, Budi, Novi Rahmawati Sutopo, and Yulia Nuraini. 2021. “Utilization of Indigenous Phosphate-Solubilizing Bacteria to Optimize the Use of Coal Fly Ash for Increasing Available-P in an Ultisol”. Journal of Degraded and Mining Lands Management 8 (4). Malang, Indonesia:2937-46. https://doi.org/10.15243/jdmlm.2021.084.2937.