| article html file updated | 5 February 2020 13:02 CET | Update | https://www.mdpi.com/1422-8599/2006/6/M504 |
| article html file updated | 18 September 2019 19:51 CEST | Update | N/A |
| article html file updated | 9 May 2019 09:30 CEST | Update | N/A |
| article html file updated | 19 March 2019 20:48 CET | Update | N/A |
| article html file updated | 23 September 2017 09:14 CEST | Update | N/A |
| article xml uploaded. | 23 September 2017 09:13 CEST | Original file | https://www.mdpi.com/1422-8599/2006/6/M504/xml |
| article html file updated | 14 December 2016 11:04 CET | Original file | N/A |
