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Submitted on: 10 June 2010.
Revised on: 06 July 2010.
Accepted on: 14 July 2010.
PUBLIC CHOICE---SPRINGER
Submitted on: 10 September 2015.
Revised on: 09 October 2015.
Accepted on: 23 October 2015.
PUBLIC CHOICE
Submitted on: 20 October 2011.
Revised on: 18 November 2011.
Accepted on: 16 December 2011.
PUBLIC CHOICE---SPRINGER