| article html file updated | 6 February 2020 15:27 CET | Update | https://www.mdpi.com/1999-4907/6/2/280 |
| article html file updated | 7 May 2019 01:55 CEST | Update | N/A |
| article html file updated | 25 March 2019 20:57 CET | Update | N/A |
| article html file updated | 21 August 2015 06:30 CEST | Original file | N/A |
| article pdf uploaded. | 26 January 2015 12:37 CET | Version of Record | https://www.mdpi.com/1999-4907/6/2/280/pdf |
