| article html file updated | 6 February 2020 23:20 CET | Update | https://www.mdpi.com/2076-0787/4/4/523 |
| article html file updated | 21 September 2019 04:12 CEST | Update | N/A |
| article html file updated | 6 May 2019 10:13 CEST | Update | N/A |
| article html file updated | 26 March 2019 11:47 CET | Original file | N/A |
| article pdf uploaded. | 29 September 2015 14:46 CEST | Version of Record | https://www.mdpi.com/2076-0787/4/4/523/pdf |
