| article html file updated | 7 February 2020 04:59 CET | Update | https://www.mdpi.com/2227-9059/4/1/7 |
| article html file updated | 5 May 2019 23:21 CEST | Update | - |
| article html file updated | 26 March 2019 21:38 CET | Update | - |
| article html file updated | 21 February 2017 08:41 CET | Update | - |
| article html file updated | 8 June 2016 09:22 CEST | Original file | - |
| article pdf uploaded. | 25 February 2016 13:31 CET | Version of Record | https://www.mdpi.com/2227-9059/4/1/7/pdf |
| article xml uploaded. | 25 February 2016 13:31 CET | Original file | https://www.mdpi.com/2227-9059/4/1/7/xml |
