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Submitted on: 09 February 2004.
Revised on: 11 April 2004.
Accepted on: 30 April 2004.
___________________Interdisciplinary Journal of Problem-Based Learning
Submitted on: 02 September 2001.
Revised on: 27 November 2001.
Accepted on: 01 January 2002.
___________________Interdisciplinary Journal of Problem-Based Learning
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