S. . T. Hussein, E. . T. Ali, K. . F. Ali, and J. . H. Tomma, “Evidence Supports The Formation Of Isoimides Derived From Pyromellitic Dianhydride”, IHJPAS, vol. 26, no. 1, pp. 241–249, Apr. 2017, Accessed: May 01, 2025. [Online]. Available: https://www.jih.uobaghdad.edu.iq/index.php/j/article/view/530