Potential Energy Expectation Value for Lithium Excited State (1s2s3s). Baghdad Science Journal, Iraq, Baghdad, v. 12, n. 2, p. 394–399, 2015. DOI: 10.21123/bsj.2015.12.2.394-399. Disponível em: https://bsj.uobaghdad.edu.iq/index.php/BSJ/article/view/2080.. Acesso em: 3 may. 2024.