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Submitted on: 23 January 2000.
Revised on: 22 May 2000.
Accepted on: 25 June 2000.
___________________International Journal for Lesson and Learning Studies
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Submitted on: 12 February 2002.
Revised on: 09 March 2002.
Accepted on: 10 April 2002.
___________________International Journal for Lesson and Learning Studies
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