Linturi, James, J Okumu, and C S Singh. “A Distorted Wave Method Applied to Study the 23 P Excitation of Helium Atom by Electron Impact”. Indonesian Journal of Physics 22, no. 2 (November 3, 2016): 35-40. Accessed November 23, 2024. https://ijphysics.fi.itb.ac.id/index.php/ijp/article/view/231.