| article html file updated | 7 February 2020 03:22 CET | Update | https://www.mdpi.com/1996-1073/9/1/42 |
| article html file updated | 6 May 2019 02:43 CEST | Update | - |
| article html file updated | 26 March 2019 18:19 CET | Original file | - |
| article pdf uploaded. | 13 January 2016 11:25 CET | Version of Record | https://www.mdpi.com/1996-1073/9/1/42/pdf |
| article xml uploaded. | 13 January 2016 11:25 CET | Original file | https://www.mdpi.com/1996-1073/9/1/42/xml |
