| article html file updated | 8 February 2020 17:16 CET | Update | https://www.mdpi.com/2223-7747/6/4/44 |
| article html file updated | 27 September 2019 09:45 CEST | Update | - |
| article html file updated | 2 May 2019 23:51 CEST | Update | - |
| article html file updated | 2 January 2018 20:20 CET | Update | - |
| article html file updated | 27 September 2017 09:18 CEST | Original file | - |
| article xml uploaded. | 27 September 2017 09:17 CEST | Original file | https://www.mdpi.com/2223-7747/6/4/44/xml |
| article pdf uploaded. | 27 September 2017 09:17 CEST | Version of Record | https://www.mdpi.com/2223-7747/6/4/44/pdf |
