1. American Society for Testing and Materials, ‘Annual Book of ASTM Standards’, Philadelphia, 1979, Parts 23–25.
2. ‘Waste Lubricating Oil, Annotated Review’, BETC/IC 79/4, 1979, p. 96.
3. Studies on the ageing characteristics of automotive crankcase oils
4. , , ‘Quality Control/Petroleum Product Specifications’, Unpublished Workshop Training Programme, Port Harcourt, Nigeria, 2006, pp. 62–68.
5. , , ‘Metals in New and Used Petroleum Products and By-Products: Quantities and Consequences’, Elsevier, 1999, pp. 124–144.