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Submitted on: 31 August 2012.
Revised on: 13 December 2012.
Accepted on: 17 January 2013.
___________________JOURNAL FOR RESEARCH IN MATHEMATICS EDUCATION
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Submitted on: 04 July 2011.
Revised on: 03 September 2011.
Accepted on: 10 October 2011.
___________________JOURNAL FOR RESEARCH IN MATHEMATICS EDUCATION
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Submitted on: 22 October 2011.
Revised on: 22 December 2011.
Accepted on: 05 January 2012.
___________________JOURNAL FOR RESEARCH IN MATHEMATICS EDUCATION