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2. Nybelin, Festskrift för Herbert Jacobsson, Göteborg, 1949, and Reports of the Swedish Deep Sea Expedition (in the press) (Göteborg, 1951).
3. Matthews, “Tables of the Velocity …”, Hydrographlc Department, Admiralty (2nd edit., London, 1939).
4. Hess and Buell, Trans. Amer. Geophys. Union, 31 (1950).