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 # Data and code files description
 
-1. [20241128_ias_union_concern_Natura2000_B.gpkg](https://github.com/inbo/coding-club/blob/master/data/20241128_ias_union_concern_Natura2000_B.gpkg): geopackage with the number of alien species of Union concern observed in the Flemish NATURA2000 protected areas, type B.
+1. [20241128_ias_union_concern_Natura2000_B.gpkg](https://github.com/inbo/coding-club/blob/master/data/20241128_ias_union_concern_Natura2000_B.gpkg)*: geopackage with the number of alien species of Union concern observed in the Flemish NATURA2000 protected areas, type B.
 2. [20241128_flemish_municipalities.gpkg](https://github.com/inbo/coding-club/blob/main/data/20241128/20241128_flemish_municipalities.gpkg): geopcakge with the Flemish municipalities.
 3. [20241128_challenges.R](https://github.com/inbo/coding-club/blob/master/src/20241128/20241128_challenges.R): R script to start from.
 
+\* Derived from a geopackage with all European Natura2000 areas: https://www.eea.europa.eu/en/datahub/datahubitem-view/6fc8ad2d-195d-40f4-bdec-576e7d1268e4
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