Study of the Singlet and the Triplet States of Two ElectronSystems in the First Excited State. Baghdad Science Journal, Iraq, Baghdad, v. 7, n. 1, p. 36–40, 2010. DOI: 10.21123/bsj.2010.7.1.36-40. Disponível em: https://bsj.uobaghdad.edu.iq/index.php/BSJ/article/view/2870.. Acesso em: 3 may. 2024.