1. S. D. Stookey andR. D. Maurer, in ?Progress in Ceramic Science?, Vol. 2, edited by J. E. Burke (Pergamon, New York, 1962) p. 77.
2. P. W. McMillan, ?Glass-Ceramics? (Academic, London, 1979).
3. M. Tashiro,Glass Indi (July 1966) 366.
4. Idem., ibid. (August 1966) 428.
5. A. W. A. El-Shennawi, PhD thesis, Cairo University (1977).