| article html file updated | 8 February 2020 03:16 CET | Update | https://www.mdpi.com/2227-9709/4/2/9 |
| article html file updated | 24 September 2019 06:00 CEST | Update | - |
| article html file updated | 4 May 2019 02:50 CEST | Update | - |
| article html file updated | 27 October 2017 10:25 CEST | Update | - |
| article html file updated | 11 April 2017 11:29 CEST | Original file | - |
| article xml uploaded. | 11 April 2017 11:28 CEST | Original file | https://www.mdpi.com/2227-9709/4/2/9/xml |
| article pdf uploaded. | 11 April 2017 11:28 CEST | Updated version of record | https://www.mdpi.com/2227-9709/4/2/9/pdf |
| article pdf uploaded. | 10 April 2017 11:56 CEST | Version of Record | https://www.mdpi.com/2227-9709/4/2/9/pdf-vor |
