1. Private communication with the Plant Manager of Best Foods Inc., Yanbu, Saudi Arabia.
2. Vegetable oils, Chapter;Hamm,1983
3. Recycling and utilization of spent bleaching earth;Ong;Fette Selen Anstrichmittel,1983
4. Hamza, A. 1966, An Investigation on the Utilization of Egyptian Clays in Bleaching of Cottonseed Oil, MSc Thesis (Alexandria University, Egypt).