| article html file updated | 24 December 2025 13:04 CET | Update | https://www.mdpi.com/1422-8599/2006/6/M520 |
| article html file updated | 24 September 2025 18:45 CEST | Update | N/A |
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| article html file updated | 23 September 2017 10:16 CEST | Update | N/A |
| article xml uploaded. | 23 September 2017 10:15 CEST | Original file | https://www.mdpi.com/1422-8599/2006/6/M520/xml |
| article html file updated | 14 December 2016 11:05 CET | Original file | N/A |
