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2. K. W. STANLEY, Mullard Limited, private communication (1974).
3. ?Components and Materials?, Philips Data Handbook, Part 2a (October 1977).
4. K. C. BHATT,IEE IERE Proc. India,11 (1973) 194.
5. S. M. SZE, ?Physics of Semiconductor Devices? (Wiley Eastern Limited, New Delhi, 1979) p. 779.