| article html file updated | 6 February 2020 13:47 CET | Update | https://www.mdpi.com/2076-0787/3/4/687 |
| article html file updated | 20 September 2019 15:06 CEST | Update | N/A |
| article html file updated | 7 May 2019 05:13 CEST | Update | N/A |
| article html file updated | 25 March 2019 18:00 CET | Original file | N/A |
| article pdf uploaded. | 19 November 2014 14:23 CET | Version of Record | https://www.mdpi.com/2076-0787/3/4/687/pdf |
