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Submitted on: 28 May 2003.
Revised on: 26 August 2003.
Accepted on: 25 September 2003.
___________________International Journal of Knowledge and Learning
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Submitted on: 18 October 2022.
Revised on: 16 December 2022.
Accepted on: 11 February 2023.
___________________International Journal of Knowledge and Learning
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