1. Recycling Oil;Becker,1984
2. Technologies for Re-refining Use;Brinkman;Lubricating Eng.,1987
3. Bright Prospects Loom for Used Oil Re-refiners;Deutsch;Chem. Eng.,1979
4. Re-refining of Waste Lube Oil;Hazewinkel,1980
5. Recycling of Used Lubricating Oil in Australia;Siemon;Conserv. Recycl.,1979