Submitted on: 29 January 2020.
Revised on: 24 April 2020.
Accepted on: 06 June 2020.
___________________Geography and Sustainability---ELSEVIER
Submitted on: 01 April 2015.
Revised on: 19 July 2015.
Accepted on: 19 August 2015.
___________________Geography and Sustainability---ELSEVIER
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Submitted on: 31 March 2010.
Revised on: 03 July 2010.
Accepted on: 12 August 2010.
___________________Geography and Sustainability---ELSEVIER
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