| article html file updated | 6 February 2020 15:05 CET | Update | https://www.mdpi.com/2073-4409/4/1/21 |
| article html file updated | 7 May 2019 02:39 CEST | Update | - |
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| article xml file uploaded | 1 April 2015 11:10 CEST | Original file | https://www.mdpi.com/2073-4409/4/1/21/xml |
| article pdf uploaded. | 9 January 2015 15:06 CET | Version of Record | https://www.mdpi.com/2073-4409/4/1/21/pdf |
