| article html file updated | 6 February 2020 05:51 CET | Update | https://www.mdpi.com/2226-4787/1/2/237 |
| article html file updated | 20 September 2019 03:44 CEST | Update | - |
| article html file updated | 7 May 2019 21:31 CEST | Update | - |
| article html file updated | 21 March 2019 08:28 CET | Update | - |
| article html file updated | 19 August 2015 11:38 CEST | Original file | - |
| article pdf uploaded. | 5 December 2013 16:09 CET | Updated version of record | https://www.mdpi.com/2226-4787/1/2/237/pdf |
| article pdf uploaded. | 28 November 2013 13:36 CET | Version of Record | https://www.mdpi.com/2226-4787/1/2/237/pdf-vor |
