| article html file updated | 8 February 2020 03:26 CET | Update | https://www.mdpi.com/2221-3759/5/2/4 |
| article html file updated | 4 May 2019 02:29 CEST | Update | - |
| article html file updated | 29 June 2017 11:32 CEST | Update | - |
| article html file updated | 12 April 2017 12:34 CEST | Original file | - |
| article xml uploaded. | 12 April 2017 12:33 CEST | Original file | https://www.mdpi.com/2221-3759/5/2/4/xml |
| article pdf uploaded. | 12 April 2017 12:33 CEST | Version of Record | https://www.mdpi.com/2221-3759/5/2/4/pdf |
