Submitted on: 31 August 2008.
Revised on: 19 December 2008.
Accepted on: 26 January 2009.
___________________JOURNAL OF COMPUTER ASSISTED LEARNING
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Submitted on: 03 January 2012.
Revised on: 17 March 2012.
Accepted on: 27 April 2012.
___________________JOURNAL OF COMPUTER ASSISTED LEARNING
http://reply.papertrans.cn/2/161/16087/16087-34.png
Submitted on: 16 September 2018.
Revised on: 06 December 2018.
Accepted on: 27 December 2018.
___________________JOURNAL OF COMPUTER ASSISTED LEARNING
Submitted on: 22 February 1998.
Revised on: 26 March 1998.
Accepted on: 04 May 1998.
___________________JOURNAL OF COMPUTER ASSISTED LEARNING