1. What makes oil different from others, and does it really matter to your engine;Moll;Flying,1992
2. Synthetic motor oil – is it worth the price;Paul,1998
3. Lubrication theory and practice – includes information on viscosity and the additives common to motor oil. http://www.lubrizol.com/referencelibrary/readyreference/4-base stocks.htm; 17th September 1997.
4. Ready reference for lubricant and fuel performance – includes detailed information on API, ILSAC, and ACEA specifications and test procedures. http://www.lubrizol.com/referencelibrary/lubtheory/base.htm; 17th September 1998.
5. Think green: biodegradable lubes glow with promise;Woods;Lubes-n-Greases,1997