Al-Bahrani, B. H., and H. S. Al-Redeeni. “Hollow Modules With Respect to an Arbitrary Submodule ”. Iraqi Journal of Science, vol. 58, no. 2A, Jan. 2022, pp. 694-8, https://ijs.uobaghdad.edu.iq/index.php/eijs/article/view/6099.