Thank you Karsten and Matti! Location is correct. Lanklaar is more or less 25km north of Maastricht. When I'm correct Fl.ÜG 1 means they were flying a factory fresh airplane to 7./KG 30? So there are a few errors on this site:
http://aviation-safety.net/wikibase/219515 All 4 crew perished in the crash and were burried at Brustem, St.-Truiden (St.-Trond).