| article html file updated | 6 February 2020 08:22 CET | Update | https://www.mdpi.com/2076-0825/3/2/20 |
| article html file updated | 7 May 2019 16:24 CEST | Update | - |
| article html file updated | 21 March 2019 14:57 CET | Original file | - |
| article pdf uploaded. | 6 May 2014 10:41 CEST | Updated version of record | https://www.mdpi.com/2076-0825/3/2/20/pdf |
| article pdf uploaded. | 3 April 2014 10:56 CEST | Version of Record | https://www.mdpi.com/2076-0825/3/2/20/pdf-vor |
