| article html file updated | 7 February 2020 09:30 CET | Update | https://www.mdpi.com/1996-1073/9/6/420 |
| article html file updated | 5 May 2019 14:13 CEST | Update | - |
| article html file updated | 27 March 2019 06:10 CET | Update | - |
| article html file updated | 28 June 2016 09:27 CEST | Update | - |
| article html file updated | 31 May 2016 11:35 CEST | Original file | - |
| article xml uploaded. | 31 May 2016 11:33 CEST | Original file | https://www.mdpi.com/1996-1073/9/6/420/xml |
| article pdf uploaded. | 31 May 2016 11:33 CEST | Version of Record | https://www.mdpi.com/1996-1073/9/6/420/pdf |
