Bhatia, A. K. “4F and 5F Excitations of Atomic Hydrogen by Electron Impact”. Journal of Atomic, Molecular, Condensed Matter and Nano Physics 12, no. 1 (October 26, 2025): 49–54. Accessed April 4, 2026. https://rgnpublications.com/journals/index.php/jamcnp/article/view/3137.