| article html file updated | 7 February 2020 21:10 CET | Update | https://www.mdpi.com/2218-1989/7/1/2 |
| article html file updated | 4 May 2019 15:58 CEST | Update | - |
| article html file updated | 30 March 2017 11:58 CEST | Update | - |
| article html file updated | 11 January 2017 10:06 CET | Original file | - |
| article xml uploaded. | 11 January 2017 10:04 CET | Original file | https://www.mdpi.com/2218-1989/7/1/2/xml |
| article pdf uploaded. | 11 January 2017 10:04 CET | Version of Record | https://www.mdpi.com/2218-1989/7/1/2/pdf |
