| article html file updated | 6 February 2020 06:18 CET | Update | https://www.mdpi.com/1996-1073/6/12/6608 |
| article html file updated | 7 May 2019 20:40 CEST | Update | - |
| article html file updated | 21 March 2019 09:43 CET | Update | - |
| article html file updated | 20 January 2017 03:27 CET | Original file | - |
| article pdf uploaded. | 18 December 2013 12:08 CET | Version of Record | https://www.mdpi.com/1996-1073/6/12/6608/pdf |
