A. H. A. Karim Mohammed, A. M. A.KARIM, and H. A.Areff, “Effect of Operating Cconditions on Hydrodesulfurization of Vacuum Gas Oil”, IJCPE, vol. 9, no. 2, pp. 57–67, Jun. 2008, doi: 10.31699/IJCPE.2008.2.7.