| article html file updated | 7 February 2020 02:33 CET | Update | https://www.mdpi.com/2076-3417/6/1/2 |
| article html file updated | 6 May 2019 04:19 CEST | Update | - |
| article html file updated | 26 March 2019 17:00 CET | Original file | - |
| article xml uploaded. | 22 December 2015 16:49 CET | Original file | https://www.mdpi.com/2076-3417/6/1/2/xml |
| article pdf uploaded. | 22 December 2015 16:06 CET | Version of Record | https://www.mdpi.com/2076-3417/6/1/2/pdf |
