| article html file updated | 6 February 2020 00:28 CET | Update | https://www.mdpi.com/2076-0752/2/1/1 |
| article html file updated | 19 September 2019 17:47 CEST | Update | N/A |
| article html file updated | 8 May 2019 08:39 CEST | Update | N/A |
| article html file updated | 20 March 2019 18:24 CET | Update | N/A |
| article html file updated | 15 February 2017 11:00 CET | Original file | N/A |
| article pdf uploaded. | 21 February 2013 09:17 CET | Updated version of record | https://www.mdpi.com/2076-0752/2/1/1/pdf |
| article pdf uploaded. | 6 February 2013 15:47 CET | Version of Record | N/A |
