Cahyonugroho, O. H. ., S. . Hariyanto, and G. Supriyanto. “Applying Fluorescence Dissolved Organic Matter Spectra and Phytoplankton Biology Index for Assessing Urban River Quality”. Journal of Mathematical and Fundamental Sciences, vol. 54, no. 3, May 2023, pp. 311-29, doi:10.5614/j.math.fund.sci.2023.54.3.3.