| article html file updated | 7 February 2020 23:19 CET | Update | https://www.mdpi.com/2223-7747/6/1/9 |
| article html file updated | 23 September 2019 07:31 CEST | Update | - |
| article html file updated | 4 May 2019 11:24 CEST | Update | - |
| article html file updated | 30 March 2017 09:40 CEST | Update | - |
| article html file updated | 14 February 2017 06:01 CET | Original file | - |
| article xml uploaded. | 14 February 2017 06:00 CET | Original file | https://www.mdpi.com/2223-7747/6/1/9/xml |
| article pdf uploaded. | 14 February 2017 06:00 CET | Version of Record | https://www.mdpi.com/2223-7747/6/1/9/pdf |
