| article html file updated | 8 February 2020 20:38 CET | Update | https://www.mdpi.com/2227-9709/4/4/38 |
| article html file updated | 2 May 2019 16:15 CEST | Update | N/A |
| article html file updated | 2 January 2018 12:47 CET | Update | N/A |
| article html file updated | 9 November 2017 11:25 CET | Original file | N/A |
| article xml uploaded. | 9 November 2017 11:23 CET | Original file | https://www.mdpi.com/2227-9709/4/4/38/xml |
| article pdf uploaded. | 9 November 2017 11:23 CET | Updated version of record | https://www.mdpi.com/2227-9709/4/4/38/pdf |
| article pdf uploaded. | 8 November 2017 13:21 CET | Version of Record | https://www.mdpi.com/2227-9709/4/4/38/pdf-vor |
