Jasim, Bilal K, Ayad A Al-Ani, and Saad. N Abood. 2018. “Using Gaussian Basis-Sets With Gaussian Nuclear Charge Distribution to Solve Dirac-Hartree-Fock Equation for 83Bi-Atom”. Al-Nahrain Journal of Science 19 (3): 70-76. https://mail.anjs.edu.iq/index.php/anjs/article/view/207.