Submitted on: 28 June 2007.
Revised on: 15 July 2007.
Accepted on: 24 July 2007.
NULL
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http://reply.papertrans.cn/3/270/26918/26918-13.png
Submitted on: 21 February 2017.
Revised on: 01 March 2017.
Accepted on: 21 March 2017.
NULL
Submitted on: 08 November 1999.
Revised on: 12 December 1999.
Accepted on: 30 December 1999.
Revista Electronica Educare---UNIV NACL, CIDE
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http://reply.papertrans.cn/3/270/26918/26918-17.png
http://reply.papertrans.cn/3/270/26918/26918-18.png
Submitted on: 06 January 2016.
Revised on: 19 January 2016.
Accepted on: 03 February 2016.
NULL
Submitted on: 15 August 2023.
Revised on: 10 September 2023.
Accepted on: 28 September 2023.
Revista Electronica Educare---UNIV NACL, CIDE