@article{Christiansen_2014, place={Copenhagen, Denmark}, title={Review of Survey activities 2013}, volume={31}, url={https://geusbulletin.org/index.php/geusb/article/view/4629}, DOI={10.34194/geusb.v31.4629}, journal={GEUS Bulletin}, author={Christiansen, F.G.}, year={2014}, month={Jun.}, pages={1–8} }