| article html file updated | 7 February 2020 05:34 CET | Update | https://www.mdpi.com/2297-8747/21/1/4 |
| article html file updated | 5 May 2019 22:10 CEST | Update | N/A |
| article html file updated | 26 March 2019 22:49 CET | Original file | N/A |
| article pdf uploaded. | 8 March 2016 08:24 CET | Version of Record | https://www.mdpi.com/2297-8747/21/1/4/pdf |
| article xml uploaded. | 8 March 2016 08:24 CET | Original file | https://www.mdpi.com/2297-8747/21/1/4/xml |
