Thanks for the links. I am actually wondering if the license (https://www.ni.is/sites/default/files/atoms/files/License-for-use-of-free-IINH-data_General-terms_20131121.pdf) is compatible with OSM. It is based on the Open Government license, but it does not state a version. If I can confirm the validity, this would be a great additional source for edits. :)