| article html file updated | 7 February 2020 22:31 CET | Update | https://www.mdpi.com/2075-4701/7/2/40 | 
| article html file updated | 23 September 2019 03:07 CEST | Update | - | 
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| article html file updated | 1 March 2017 03:45 CET | Update | - | 
| article html file updated | 13 February 2017 04:10 CET | Original file | - | 
| article xml uploaded. | 13 February 2017 04:09 CET | Update | https://www.mdpi.com/2075-4701/7/2/40/xml | 
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| article pdf uploaded. | 13 February 2017 04:09 CET | Updated version of record | https://www.mdpi.com/2075-4701/7/2/40/pdf | 
| article pdf uploaded. | 31 January 2017 10:42 CET | Version of Record | https://www.mdpi.com/2075-4701/7/2/40/pdf-vor |