A. Mohammed, A.-H. and J. Yass Kheder, M. 2009. The Effect of Extraction Temperature and Solvent to Oil Ratio on Viscosity Index of Mixed-medium Lubricating Oil Fraction by Using Solvents Extraction. Iraqi Journal of Chemical and Petroleum Engineering. 10, 2 (Jun. 2009), 13–18. DOI:https://doi.org/10.31699/IJCPE.2009.2.3.