| article html file updated | 7 February 2020 02:47 CET | Update | https://www.mdpi.com/2077-1444/7/1/4 |
| article html file updated | 6 May 2019 03:46 CEST | Update | N/A |
| article html file updated | 26 March 2019 17:23 CET | Original file | N/A |
| article pdf uploaded. | 28 December 2015 13:25 CET | Version of Record | https://www.mdpi.com/2077-1444/7/1/4/pdf |
