H. Sh. Al-Obaidi, Omar. “Spectroscopic Characterization and Theoretical Treatment of Tetradentate Macrocyclic Ligand and Its Transition Metal Complexes”. Asian Journal of Chemistry 24, no. 7 (March 12, 2012): 2989–2992. Accessed July 22, 2024. https://asianpubs.org/index.php/ajchem/article/view/9277.