| article html file updated | 8 February 2020 20:47 CET | Update | https://www.mdpi.com/2076-0787/6/4/87 |
| article html file updated | 28 September 2019 08:52 CEST | Update | - |
| article html file updated | 2 May 2019 15:54 CEST | Update | - |
| article html file updated | 9 November 2017 16:03 CET | Original file | - |
| article xml uploaded. | 9 November 2017 16:02 CET | Update | https://www.mdpi.com/2076-0787/6/4/87/xml |
| article xml uploaded. | 9 November 2017 16:02 CET | Update | - |
| article xml uploaded. | 9 November 2017 16:02 CET | Original file | - |
| article pdf uploaded. | 9 November 2017 16:02 CET | Version of Record | https://www.mdpi.com/2076-0787/6/4/87/pdf |
