Ginting, Ina Febria, et al. “Remediation Of Lead and Cadmium Contaminated Soil Using Fly Ash and Organic Materials”. Jurnal Ilmu Tanah Dan Lingkungan, vol. 26, no. 2, Oct. 2024, pp. 66-71, https://doi.org/10.29244/jitl.26.2.66-71.