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2. Vegetational change along altitudinal gradients;Beals;Science,1969
3. Data on humus in podzolic and sod-podzolic., natural and cultivated soils in the European part of the USSR;Bel'chikova,1970
4. Interaction of vegetation and soil frost phenomena;Benninghoff;Arctic,1952
5. The structure and floristic composition of a virgin hemlock forest in West Virginia;Beri;Castanea,1965