| article html file updated | 7 February 2020 02:47 CET | Update | https://www.mdpi.com/1996-1073/9/1/18 |
| article html file updated | 6 May 2019 03:46 CEST | Update | N/A |
| article html file updated | 26 March 2019 17:23 CET | Original file | N/A |
| article pdf uploaded. | 28 December 2015 13:21 CET | Version of Record | https://www.mdpi.com/1996-1073/9/1/18/pdf |
| article xml uploaded. | 28 December 2015 13:21 CET | Original file | https://www.mdpi.com/1996-1073/9/1/18/xml |
