Submitted on: 25 April 2005.
Revised on: 15 May 2005.
Accepted on: 29 May 2005.
Portuguese Economic Journal
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Submitted on: 22 September 2008.
Revised on: 04 November 2008.
Accepted on: 17 November 2008.
Portuguese Economic Journal---SPRINGER HEIDELBERG
Submitted on: 12 December 2006.
Revised on: 04 January 2007.
Accepted on: 01 February 2007.
Portuguese Economic Journal---SPRINGER HEIDELBERG
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Submitted on: 01 February 2020.
Revised on: 23 February 2020.
Accepted on: 16 March 2020.
Portuguese Economic Journal---SPRINGER HEIDELBERG