| article html file updated | 7 February 2020 18:54 CET | Update | https://www.mdpi.com/2227-9091/4/4/44 |
| article html file updated | 22 September 2019 08:06 CEST | Update | - |
| article html file updated | 4 May 2019 20:45 CEST | Update | - |
| article html file updated | 28 December 2016 07:48 CET | Update | - |
| article html file updated | 8 December 2016 13:03 CET | Original file | - |
| article xml uploaded. | 8 December 2016 13:02 CET | Original file | https://www.mdpi.com/2227-9091/4/4/44/xml |
| article pdf uploaded. | 8 December 2016 13:02 CET | Updated version of record | https://www.mdpi.com/2227-9091/4/4/44/pdf |
| article pdf uploaded. | 30 November 2016 16:01 CET | Version of Record | https://www.mdpi.com/2227-9091/4/4/44/pdf-vor |