“Polyether Hexadentate Schiff Base Ligand with Trivalent Chromium, Iron, Cobalt Ions”, ANJS, vol. 20, no. 4, pp. 1–6, Dec. 2017, Accessed: Apr. 29, 2024. [Online]. Available: https://www.anjs.edu.iq/index.php/anjs/article/view/115