| article html file updated | 6 February 2020 06:22 CET | Update | https://www.mdpi.com/2304-8158/3/1/13 |
| article html file updated | 7 May 2019 20:32 CEST | Update | - |
| article html file updated | 21 March 2019 09:55 CET | Update | - |
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| article html file updated | 19 August 2015 14:43 CEST | Original file | - |
| article pdf uploaded. | 23 December 2013 09:45 CET | Version of Record | https://www.mdpi.com/2304-8158/3/1/13/pdf |
