K. Mheemeed, Ahmad. “Calculation of Energy Levels and The Reduced Transitions Probability For Even-Even Number of Isotones ( N=90)”. Journal of Education and Science (JES) 21, no. 4 (December 1, 2008): 97–113. Accessed August 7, 2025. https://ojs.uomosul.edu.iq/index.php/edusj/article/view/24260.