Geophysics of the polar regions : selected papers from the Symposium ... Hamburg, 23.-24.8.1983 - Johnson, G. L.; Kristoffersen, Y.; Husebye, E. S.; Symposium on Geophysics of the Polar Regions, I.U.G.G. 18th General Assembly, (Hamburg, 1983,) (Amsterdam : Elsevier, 1985)