Edris, J., N. Gupta, and E. Zereffa. “Synthesis of Silica Supported Iron Oxide Nanoparticles for Hexavalent Chromium Removal from Aqueous Solutions”. Ethiopian Journal of Science and Sustainable Development, Vol. 6, no. 2, Oct. 2019, pp. 81 -93, doi:10.20372/ejssdastu:v6.i2.2019.109.