| article html file updated | 6 February 2020 02:33 CET | Update | https://www.mdpi.com/2071-1050/5/6/2557 |
| article html file updated | 19 September 2019 21:37 CEST | Update | - |
| article html file updated | 8 May 2019 04:13 CEST | Update | - |
| article html file updated | 20 March 2019 23:37 CET | Update | - |
| article html file updated | 17 June 2015 10:05 CEST | Original file | - |
| article pdf uploaded. | 7 June 2013 11:33 CEST | Version of Record | https://www.mdpi.com/2071-1050/5/6/2557/pdf |
