Feroze, D. N., M. Rustam, A. Khan, M. Kazmi, and T. AKhtar. “Performance Evaluation of API Grade Lube Oils in Internal Combustion Engine”. Journal of the Pakistan Institute of Chemical Engineers, vol. 42, no. 2, Aug. 2014, pp. 125-32, http://piche.org.pk/journal/index.php/jpiche/article/view/143.