B. . Supriadi, H. . Mardhiana, W. I. . Kristiawan, D. . Kamalia, and I. K. . Sari, “Expected Value of Helium Ion Electron Momentum in Momentum Space with Primary Quantum Numbers n≤3”, jppipa, pendidikan ipa, fisika, biologi, kimia, vol. 9, no. 10, pp. 8467–8472, Oct. 2023.