| article html file updated | 7 February 2020 22:36 CET | Update | https://www.mdpi.com/2218-1989/7/1/6 |
| article html file updated | 23 September 2019 03:28 CEST | Update | - |
| article html file updated | 4 May 2019 12:51 CEST | Update | - |
| article html file updated | 30 March 2017 11:59 CEST | Update | - |
| article html file updated | 4 February 2017 05:51 CET | Original file | - |
| article pdf uploaded. | 3 February 2017 13:08 CET | Version of Record | https://www.mdpi.com/2218-1989/7/1/6/pdf |
