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Submitted on: 08 May 2019.
Revised on: 07 August 2019.
Accepted on: 04 September 2019.
___________________Frontiers in Sustainable Cities
Submitted on: 02 September 2015.
Revised on: 20 December 2015.
Accepted on: 17 January 2016.
___________________Frontiers in Sustainable Cities
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