Abdullal, H. M. A., and Luma J. Barghooth. “On The Intersection of Semi-Pure Subgroups of Abelian Group”. Iraqi Journal of Science (May 17, 2020): 196–199. Accessed June 26, 2026. https://www.ijs.uobaghdad.edu.iq/index.php/eijs/article/view/2252.