Mohamed H. A. Hamed, Islam F. M. Osman, Mohammed B.A. Mohammad, Arafat Abdelhameed Abdelrahmann and Asmaa Eltayeb Ali Elhassan 2022. Contact Lorentzian Manifolds of Constant Curvature and CR-Manifolds. Journal of The Faculty of Science and Technology. 8 (Feb. 2022), 113 - 120. DOI:https://doi.org/10.52981/jfst.vi8.1967.