| article html file updated | 6 February 2020 05:53 CET | Update | https://www.mdpi.com/2304-8158/2/4/554 |
| article html file updated | 7 May 2019 21:27 CEST | Update | - |
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| article html file updated | 19 August 2015 11:48 CEST | Original file | - |
| article pdf uploaded. | 29 November 2013 15:26 CET | Version of Record | https://www.mdpi.com/2304-8158/2/4/554/pdf |
