Christoffersen, K., Arboe, N. H.
, Landkildehus, F., Jeppesen, E., Søndergaard, M. & Rasch, M. (red.) (1999).
Studies of Lepidurus arcticus. I M. Rasch (red.),
Zackenberg Ecological Research Operations, 4th Annual Report 1998 (s. 45-46). Danish Polar Center.
Laubel, A., Jacobsen, O. H.
, Kronvang, B., Grant, R. & Andersen, H. E. (1999).
Subsurface Drainage Loss of Particles and Phosphorus from Field Plot Experiments and a Tile-Drained Catchment.
Journal of Environmental Quality,
28(2), 576-584.
Birkenmayer, A., Müller-Wohlfeil, D.-I., Demuth, S.
, Kronvang, B. & Budesanstalt für Gewässerkunde IHP/OHP (red.) (1999).
The ERICA 1 : 250K Pilot Databases. I Budesanstalt für Gewässerkunde IHP/OHP (red.),
International Conference on Quality, Management and Availability of Data for Hydrology and Water Resources Management, Koblenz, Federal Republic of Germany, March 22-26, 1999 (s. 143-146). Koblenz: Deutsches Nationalkomitee für das IHP/OHP.