| article html file updated | 6 February 2020 13:28 CET | Update | https://www.mdpi.com/2223-7747/3/4/476 |
| article html file updated | 7 May 2019 05:51 CEST | Update | N/A |
| article html file updated | 25 March 2019 17:18 CET | Update | N/A |
| article html file updated | 21 August 2015 01:30 CEST | Original file | N/A |
| article pdf uploaded. | 7 November 2014 12:23 CET | Version of Record | https://www.mdpi.com/2223-7747/3/4/476/pdf |
