| article html file updated | 6 February 2020 04:29 CET | Update | https://www.mdpi.com/1996-1073/6/9/4897 |
| article html file updated | 8 May 2019 00:14 CEST | Update | - |
| article html file updated | 21 March 2019 04:48 CET | Update | - |
| article html file updated | 17 February 2017 06:07 CET | Original file | - |
| article pdf uploaded. | 23 September 2013 10:00 CEST | Version of Record | https://www.mdpi.com/1996-1073/6/9/4897/pdf |
