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Submitted on: 17 February 2001.
Revised on: 03 June 2001.
Accepted on: 30 July 2001.
___________________JOURNAL OF SCIENTIFIC & INDUSTRIAL RESEARCH
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Submitted on: 16 July 2002.
Revised on: 24 September 2002.
Accepted on: 10 October 2002.
___________________JOURNAL OF SCIENTIFIC & INDUSTRIAL RESEARCH
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