Submitted on: 10 January 2001.
Revised on: 19 January 2001.
Accepted on: 29 January 2001.
Revista Finanzas y Politica Economica
http://reply.papertrans.cn/3/270/26958/26958-32.png
Submitted on: 15 April 2010.
Revised on: 25 May 2010.
Accepted on: 31 May 2010.
NULL
http://reply.papertrans.cn/3/270/26958/26958-34.png
Submitted on: 17 May 2011.
Revised on: 01 June 2011.
Accepted on: 21 June 2011.
NULL
Submitted on: 24 April 2012.
Revised on: 05 May 2012.
Accepted on: 30 May 2012.
Revista Finanzas y Politica Economica