Submitted on: 17 May 2008.
Revised on: 29 June 2008.
Accepted on: 28 August 2008.
___________________COMPUTERS & EDUCATION---PERGAMON-ELSEVIER SCIENCE LTD
Submitted on: 11 September 2005.
Revised on: 20 October 2005.
Accepted on: 18 December 2005.
___________________COMPUTERS & EDUCATION---PERGAMON-ELSEVIER SCIENCE LTD
Submitted on: 18 August 2009.
Revised on: 23 September 2009.
Accepted on: 05 November 2009.
___________________COMPUTERS & EDUCATION---PERGAMON-ELSEVIER SCIENCE LTD
Submitted on: 12 December 2014.
Revised on: 03 February 2015.
Accepted on: 15 February 2015.
___________________COMPUTERS & EDUCATION---PERGAMON-ELSEVIER SCIENCE LTD
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Submitted on: 30 November 2007.
Revised on: 30 January 2008.
Accepted on: 19 March 2008.
___________________COMPUTERS & EDUCATION---PERGAMON-ELSEVIER SCIENCE LTD