MAINGI, FRANCIS, Margaret Mwihaki Ng’ang’a, Harun Mbatha Mbuvi, and Henry Mwangi. 2019. “Clay-Rice Husk Ash Based Geopolymers for Remediation of Pb (II) and Cd (II) from Wastewater”. Egerton Journal of Science and Technology 17 (1-139):15-28. https://eujournal.egerton.ac.ke/index.php/EJ/article/view/35.