Abbass, H. H., Kadhim, S. A.-H. and Battor, A. H. (2020) “On Normal Subgroups Lattice of Dihedral Group”, Journal of Al-Qadisiyah for Computer Science and Mathematics, 12(1), pp. Math Page 83– 95. doi: 10.29304/jqcm.2020.12.1.675.