Galsan T. Kamal, Abdul Hakim Sh. Mohammed, and N. K. Hassan. “Study the Spectral Properties of the Molecule [Pentacene (C22H14)] by Using Semi-Empirical Quantum Programs”. Tikrit Journal of Pure Science 23, no. 3 (May 22, 2018): 133–144. Accessed September 10, 2025. https://www.tjpsj.org/index.php/tjps/article/view/510.