ABBAS, Sahar F.; ALI, Emad T.; TOMMA, Jumbad H. Synthesis and Characterization of New Heterocyclic Derived from Pyromellitic Dianhydride. Ibn AL-Haitham Journal For Pure and Applied Sciences, Baghdad, Iraq., v. 26, n. 3, p. 268–280, 2017. Disponível em: https://jih.uobaghdad.edu.iq/index.php/j/article/view/438. Acesso em: 28 mar. 2025.