| article html file updated | 7 February 2020 03:13 CET | Update | https://www.mdpi.com/2077-1444/7/1/9 |
| article html file updated | 6 May 2019 02:59 CEST | Update | - |
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| article xml uploaded. | 8 January 2016 15:29 CET | Original file | https://www.mdpi.com/2077-1444/7/1/9/xml |
| article pdf uploaded. | 8 January 2016 15:29 CET | Version of Record | https://www.mdpi.com/2077-1444/7/1/9/pdf |
