Po Cheng, W., Tsang Lu, Y., Fang Yu, R., Ru Lin, X., & Xin Li, H. (2018). Finding the Reaction Constant Between Humic Acid and Metal Ions by Fluorescence Quenching Effect. International Journal of Engineering & Technology, 7(3.32), 4-6. https://doi.org/10.14419/ijet.v7i3.32.18379