| article html file updated | 7 February 2020 08:39 CET | Update | https://www.mdpi.com/1999-5903/8/2/21 |
| article html file updated | 5 May 2019 15:53 CEST | Update | N/A |
| article html file updated | 27 March 2019 04:37 CET | Update | N/A |
| article html file updated | 16 May 2016 23:08 CEST | Original file | N/A |
| article xml uploaded. | 13 May 2016 15:55 CEST | Original file | https://www.mdpi.com/1999-5903/8/2/21/xml |
| article pdf uploaded. | 13 May 2016 15:55 CEST | Version of Record | https://www.mdpi.com/1999-5903/8/2/21/pdf |
