| article html file updated | 7 February 2020 02:39 CET | Update | https://www.mdpi.com/1999-4907/7/1/4 |
| article html file updated | 6 May 2019 04:06 CEST | Update | - |
| article html file updated | 26 March 2019 17:09 CET | Original file | - |
| article pdf uploaded. | 28 December 2015 10:21 CET | Updated version of record | https://www.mdpi.com/1999-4907/7/1/4/pdf |
| article xml uploaded. | 28 December 2015 10:21 CET | Original file | https://www.mdpi.com/1999-4907/7/1/4/xml |
| article pdf uploaded. | 24 December 2015 15:02 CET | Version of Record | https://www.mdpi.com/1999-4907/7/1/4/pdf-vor |
