M. Issa, Zainab, et al. “Electrosorption of Hexavalent Chromium Ions by MnO2 Carbon Fiber Composite Electrode: Analysis and Optimization of the Process by Box-Behnken Design”. Iraqi Journal of Chemical and Petroleum Engineering, vol. 24, no. 1, Mar. 2023, pp. 51-63, https://doi.org/10.31699/IJCPE.2023.1.7.