| article html file updated | 6 February 2020 14:15 CET | Update | https://www.mdpi.com/2304-8158/3/4/622 |
| article html file updated | 7 May 2019 04:23 CEST | Update | - |
| article html file updated | 25 March 2019 18:53 CET | Update | - |
| article html file updated | 16 February 2017 03:43 CET | Update | - |
| article html file updated | 21 August 2015 03:37 CEST | Original file | - |
| article pdf uploaded. | 5 December 2014 15:35 CET | Version of Record | https://www.mdpi.com/2304-8158/3/4/622/pdf |
