| article html file updated | 6 February 2020 08:43 CET | Update | https://www.mdpi.com/2076-3921/3/2/309 |
| article html file updated | 7 May 2019 15:39 CEST | Update | N/A |
| article html file updated | 21 March 2019 15:48 CET | Original file | N/A |
| article pdf uploaded. | 24 April 2014 16:34 CEST | Updated version of record | https://www.mdpi.com/2076-3921/3/2/309/pdf |
| article pdf uploaded. | 21 April 2014 11:10 CEST | Version of Record | https://www.mdpi.com/2076-3921/3/2/309/pdf-vor |
