Charles, D. et al. (2025) “Effect of Particle Size, NaOH Concentration, and S/L Ratio on the Extraction of Humic Acid from Leonardite”, Journal of BioProcess and Chemical Technology (JBCT), 17(34), pp. 27–34. Available at: https://revistas.uadec.mx/JBCT/article/view/196 (Accessed: 11 July 2026).