| article html file updated | 6 February 2020 02:28 CET | Update | https://www.mdpi.com/2220-9964/2/2/507 |
| article html file updated | 8 May 2019 04:25 CEST | Update | N/A |
| article html file updated | 20 March 2019 23:23 CET | Update | N/A |
| article html file updated | 17 June 2015 09:57 CEST | Original file | N/A |
| article pdf uploaded. | 4 June 2013 09:57 CEST | Version of Record | https://www.mdpi.com/2220-9964/2/2/507/pdf |
