Submitted on: 21 April 2016.
Revised on: 16 May 2016.
Accepted on: 02 July 2016.
___________________Gospodarka Narodowa-The Polish Journal of Economics
Submitted on: 29 August 2017.
Revised on: 15 November 2017.
Accepted on: 03 December 2017.
___________________Gospodarka Narodowa-The Polish Journal of Economics
Submitted on: 25 March 2011.
Revised on: 28 April 2011.
Accepted on: 30 May 2011.
___________________Gospodarka Narodowa-The Polish Journal of Economics
Submitted on: 21 March 2001.
Revised on: 26 April 2001.
Accepted on: 12 June 2001.
___________________Gospodarka Narodowa-The Polish Journal of Economics
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Submitted on: 13 May 2013.
Revised on: 17 June 2013.
Accepted on: 17 July 2013.
___________________Gospodarka Narodowa-The Polish Journal of Economics