Dinkelbach, Fabian, and Christel Maria Marian. “Vibronic and spin–orbit Coupling Effects in the Absorption Spectra of Pyrazine: A Quantum Chemical Approach”. Journal of the Serbian Chemical Society 84, no. 8 (August 29, 2019): 819–836. Accessed April 28, 2024. https://www.shd-pub.org.rs/index.php/JSCS/article/view/8182.