| article html file updated | 6 February 2020 00:33 CET | Update | https://www.mdpi.com/1996-1073/6/2/973 |
| article html file updated | 8 May 2019 08:27 CEST | Update | N/A |
| article html file updated | 20 March 2019 18:38 CET | Update | N/A |
| article html file updated | 13 February 2017 02:27 CET | Original file | N/A |
| article pdf uploaded. | 13 February 2013 16:30 CET | Version of Record | https://www.mdpi.com/1996-1073/6/2/973/pdf |
