Al-Taweel, H.H., M.J. Ali, and K.M. Al-Azawi. 2017. “Separation of Cobalt from Spent Catalyst CoMo by Precipitation and Ion Exchange Techniques”. Ibn AL-Haitham Journal For Pure and Applied Sciences 22 (2). https://jih.uobaghdad.edu.iq/index.php/j/article/view/1234.