1. 1) “Refractories manual,” American Foundrymen's Society, Inc. Des Plaines, Illinois 60016-2277 (1989).
2. 2) Shaw, K., “Classification of refractories,” Hand book of refractories and their uses, Applied Science Publishers Ltd., London (1972) pp. 74-75.
3. 3) Refractories products-classification of dense shaped refractory products, ISO 1109 (1975).
4. 4) Classification of shaped heat-insulating refractory products, ASTM C155-88 (92).
5. 5) Coope, B., “The world magnesia industry,” Ind. Min., [2], 21-31 & 43-48 (1987).