M. Abdulrasool, Jinan, Emad T. Ali, and Jumbad H. Tomma. 2017. “New Schiff – Bases Prepared From Pyromellitic Dianhydride Via Its Hydrazide Derivative”. Ibn AL-Haitham Journal For Pure and Applied Sciences 29 (1). https://jih.uobaghdad.edu.iq/index.php/j/article/view/38.