| article html file updated | 7 February 2020 03:47 CET | Update | https://www.mdpi.com/1996-1073/9/2/68 |
| article html file updated | 6 May 2019 01:54 CEST | Update | N/A |
| article html file updated | 26 March 2019 19:09 CET | Original file | N/A |
| article pdf uploaded. | 22 January 2016 12:02 CET | Version of Record | https://www.mdpi.com/1996-1073/9/2/68/pdf |
| article xml uploaded. | 22 January 2016 12:02 CET | Original file | https://www.mdpi.com/1996-1073/9/2/68/xml |
