Hayat, N., H. U. Mughal, H. Z. Nabiand, and G. Moeenuddin. “Impact of Natural Gas and Biogas on Engine Lube Oil Condition”. The Nucleus 54, no. 2 (June 30, 2017): 83–89. Accessed November 22, 2024. http://202.83.167.189/index.php/Nucleus/article/view/58.