1. United States Department of Agriculture: In: Agricultural Statistics 2000, Eds. United States Government Printing Office, Washington (USA) 2000, pp. III-26.
2. The Disposal of Used Frying Oils
3. Effective Utilization of Waste Edible Oil
4. B. Gebhardt: Oils and Fats in Snack Foods. In: Bailey's Industrial Oil & Fat Products. Vol. 3, 5th edn., Eds. Y. H. Hui. John Wiley & Sons Inc. New York (USA) 1996, pp. 407-427.
5. M. M. Blumenthal: Frying Technology. In: Bailey's Industrial Oil & Fat Products. Vol. 3, 5th edn. Eds. Y. H. Hui. John Wiley & Sons Inc. New York (USA) 1996, pp. 429-481.