Shihab, M. S. (2006) “Semi - empirical molecular orbital and UV- Visible study of the Charge transfer complex of 1- ethyl -4- (methoxycarbonyl) pyridinium iodide”, Al-Nahrain Journal of Science, 9(1), pp. 29-33. Available at: https://anjs.edu.iq/index.php/anjs/article/view/1689 (Accessed: 28August2021).