Submitted on: 18 February 1998.
Revised on: 19 March 1998.
Accepted on: 28 March 1998.
SaberEs---UNIV NACL ROSARIO, FAC CIENCIAS ECONOMICAS & ESTADISTICA
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Submitted on: 19 June 2019.
Revised on: 24 July 2019.
Accepted on: 11 August 2019.
NULL
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Submitted on: 26 March 2010.
Revised on: 25 April 2010.
Accepted on: 30 April 2010.
NULL
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Submitted on: 09 February 2010.
Revised on: 06 March 2010.
Accepted on: 30 March 2010.
SaberEs---UNIV NACL ROSARIO, FAC CIENCIAS ECONOMICAS & ESTADISTICA
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http://reply.papertrans.cn/3/275/27421/27421-29.png
Submitted on: 26 November 2005.
Revised on: 20 December 2005.
Accepted on: 16 January 2006.
SaberEs---UNIV NACL ROSARIO, FAC CIENCIAS ECONOMICAS & ESTADISTICA