Li, Chungang, and Zhihong Wang. “First Principles Studies on One-Photon and Two-Photon Absorption Properties of Symmetric Thiophene Derivatives”. Asian Journal of Chemistry 26, no. 13 (June 26, 2014): 3941–3945. Accessed July 23, 2024. https://asianpubs.org/index.php/ajchem/article/view/26_14_40.