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http://reply.papertrans.cn/3/273/27221/27221-32.png
Submitted on: 07 July 2001.
Revised on: 01 August 2001.
Accepted on: 09 August 2001.
RIE-Revista de Investigacion Educativa
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Submitted on: 01 September 2002.
Revised on: 25 September 2002.
Accepted on: 01 October 2002.
RIE-Revista de Investigacion Educativa
Submitted on: 20 May 2017.
Revised on: 09 June 2017.
Accepted on: 15 June 2017.
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