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 21, no. 4 (December 1, 2008): 97–113. Accessed September 10, 2025. https://edusj.uomosul.edu.iq/index.php/edusj/article/view/42396.