Othman, Farhad M., Alaa A. Abdul-hamead, and Noor M. Ali. 2017. “Fabrication and Characterization of Tri Metal Oxides by Chemical Spray Pyrolysis Technique As a Gas Sensor”. Al-Khwarizmi Engineering Journal 12 (4): 132-40. https://doi.org/10.22153/kej.2016.05.007.