| article html file updated | 6 February 2020 01:38 CET | Update | https://www.mdpi.com/2079-9276/2/2/39 |
| article html file updated | 19 September 2019 19:50 CEST | Update | N/A |
| article html file updated | 8 May 2019 06:03 CEST | Update | N/A |
| article html file updated | 20 March 2019 21:18 CET | Update | N/A |
| article html file updated | 17 June 2015 08:36 CEST | Original file | N/A |
| article pdf uploaded. | 7 May 2013 16:43 CEST | Updated version of record | https://www.mdpi.com/2079-9276/2/2/39/pdf |
| article pdf uploaded. | 19 April 2013 14:33 CEST | Version of Record | https://www.mdpi.com/2079-9276/2/2/39/pdf-vor |
