| article html file updated | 7 February 2020 03:53 CET | Update | https://www.mdpi.com/2079-9268/6/1/2 |
| article html file updated | 6 May 2019 01:43 CEST | Update | - |
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| article xml uploaded. | 26 January 2016 09:49 CET | Original file | https://www.mdpi.com/2079-9268/6/1/2/xml |
| article pdf uploaded. | 26 January 2016 09:49 CET | Version of Record | https://www.mdpi.com/2079-9268/6/1/2/pdf |
