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Submitted on: 16 July 2002.
Revised on: 07 September 2002.
Accepted on: 24 September 2002.
___________________JOURNAL OF ECONOMIC LITERATURE
Submitted on: 14 April 2004.
Revised on: 03 June 2004.
Accepted on: 20 July 2004.
___________________JOURNAL OF ECONOMIC LITERATURE
Submitted on: 19 March 2003.
Revised on: 01 July 2003.
Accepted on: 11 August 2003.
___________________JOURNAL OF ECONOMIC LITERATURE
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Submitted on: 29 April 2005.
Revised on: 22 July 2005.
Accepted on: 12 September 2005.
___________________JOURNAL OF ECONOMIC LITERATURE
Submitted on: 31 May 2009.
Revised on: 28 June 2009.
Accepted on: 25 July 2009.
___________________JOURNAL OF ECONOMIC LITERATURE