| article html file updated | 5 February 2020 17:04 CET | Update | https://www.mdpi.com/2071-1050/3/4/666 |
| article html file updated | 8 January 2020 13:33 CET | Update | - |
| article html file updated | 19 September 2019 03:58 CEST | Update | - |
| article html file updated | 9 May 2019 01:15 CEST | Update | - |
| article html file updated | 20 March 2019 07:01 CET | Update | - |
| article html file updated | 16 June 2015 15:33 CEST | Update | - |
| article html file updated | 6 February 2013 20:43 CET | Update | - |
| article html file updated | 6 February 2013 00:35 CET | Update | - |
| article html file updated | 28 January 2013 22:02 CET | Update | - |
| article html file updated | 26 January 2013 02:08 CET | Update | - |
| article html file updated | 22 January 2013 14:29 CET | Original file | - |