4Raiagopalan P. Gas engine emission tren&, lubrication and its challenges [R].The 14th annual fuels&lubes Asia conference, 2008.
5Walter R Pyle, Nancy R Smrcha. The Effect of Lubricating Oil Additives on Valve Recession in Stationary Gaseous-Fueled Four-Cycle Engines[R]. SAE932780, 1993.
6Dr.Ahmad Zareh. AN OVERVIEW OF INDUSTRIAL GAS ENGINES AND THEIR LUBRICATION[J]. LUBRICATION ENGINEERING, 1996, (10) : 798-808.