| article html file updated | 13 August 2026 06:08 CEST | Update | https://www.mdpi.com/1999-5903/6/4/640 |
| article html file updated | 6 February 2020 13:13 CET | Update | N/A |
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| article html file updated | 21 August 2015 00:43 CEST | Original file | N/A |
| article pdf uploaded. | 29 October 2014 09:44 CET | Version of Record | https://www.mdpi.com/1999-5903/6/4/640/pdf |
