Synthesis and Characterization of New Heterocyclic Derived from Pyromellitic Dianhydride. Ibn AL-Haitham Journal For Pure and Applied Sciences, [S. l.], v. 26, n. 3, p. 268–280, 2017. Disponível em: https://jih.uobaghdad.edu.iq/index.php/j/article/view/438.. Acesso em: 2 may. 2024.