| article html file updated | 6 February 2020 02:23 CET | Update | https://www.mdpi.com/2073-4344/3/2/517 |
| article html file updated | 8 May 2019 04:34 CEST | Update | - |
| article html file updated | 20 March 2019 23:11 CET | Update | - |
| article html file updated | 17 June 2015 09:48 CEST | Original file | - |
| article pdf uploaded. | 29 May 2013 15:13 CEST | Version of Record | https://www.mdpi.com/2073-4344/3/2/517/pdf |
