| article html file updated | 6 February 2020 15:50 CET | Update | https://www.mdpi.com/2227-9075/2/1/66 |
| article html file updated | 7 May 2019 01:13 CEST | Update | N/A |
| article html file updated | 25 March 2019 21:34 CET | Update | N/A |
| article html file updated | 21 August 2015 07:19 CEST | Original file | N/A |
| article pdf uploaded. | 9 February 2015 14:33 CET | Version of Record | https://www.mdpi.com/2227-9075/2/1/66/pdf |
