1. ILSAC GF-3 Minimum Performance Standard for Passenger Car Engine Oils, proposed August 1998, final October 2000.
2. , , , , , and , ‘Sequence VIB engine test for evaluation of fuel efficiency of engine oils, Part I: Aging procedure for determination of fuel efficiency retention’, SAE Paper 982623, 1998.
3. , , and , ‘Sequence VIB engine test for evaluation of fuel efficiency of engine oils, Part II: Stage selection and time factor determination’, SAE Paper 982624, 1998.
4. , and , ‘Fuel efficiency of SAE 5W-20 friction modified gasoline engine oil’, SAE Paper 982506, 1998.