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Submitted on: 26 November 2005.
Revised on: 16 February 2006.
Accepted on: 12 March 2006.
___________________Global Social Welfare---SPRINGER INT PUBL AG
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Submitted on: 20 February 2019.
Revised on: 20 April 2019.
Accepted on: 03 June 2019.
___________________Global Social Welfare---SPRINGER INT PUBL AG
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