Submitted on: 26 May 2003.
Revised on: 14 June 2003.
Accepted on: 29 June 2003.
South African Journal of Education
Submitted on: 14 August 2006.
Revised on: 21 September 2006.
Accepted on: 27 September 2006.
South African Journal of Education
Submitted on: 04 May 2008.
Revised on: 19 May 2008.
Accepted on: 05 June 2008.
South African Journal of Education
Submitted on: 12 December 2009.
Revised on: 31 December 2009.
Accepted on: 27 January 2010.
South African Journal of Education
Submitted on: 20 October 2011.
Revised on: 01 November 2011.
Accepted on: 18 November 2011.
South African Journal of Education
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