“Synthesis and Characterization of New Heterocyclic Derived from Pyromellitic Dianhydride” (2017) Ibn AL-Haitham Journal For Pure and Applied Sciences, 26(3), pp. 268–280. Available at: https://jih.uobaghdad.edu.iq/index.php/j/article/view/438 (Accessed: 2 May 2024).