| article html file updated | 6 February 2020 01:39 CET | Update | https://www.mdpi.com/1996-1073/6/4/2305 |
| article html file updated | 8 May 2019 06:00 CEST | Update | - |
| article html file updated | 20 March 2019 21:22 CET | Update | - |
| article html file updated | 19 April 2017 11:30 CEST | Original file | - |
| article pdf uploaded. | 22 April 2013 11:54 CEST | Version of Record | https://www.mdpi.com/1996-1073/6/4/2305/pdf |
