| article html file updated | 6 February 2020 00:16 CET | Update | https://www.mdpi.com/1996-1073/6/2/619 |
| article html file updated | 8 May 2019 09:10 CEST | Update | N/A |
| article html file updated | 20 March 2019 17:53 CET | Update | N/A |
| article html file updated | 17 February 2017 05:59 CET | Original file | N/A |
| article pdf uploaded. | 28 January 2013 16:42 CET | Version of Record | https://www.mdpi.com/1996-1073/6/2/619/pdf |
