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(6) Sampson, Arthur W. 



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(7) Shantz, H. Iv. 



1906. A STUDY OP the vegetation OF THE MESA REGION EAST OF PIKES PEAK. 

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I9II. NATURAL VEGETATION AS AN INDICATOR OF THE CAPABILITIES OF LAND 

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Bur. Plant Indus. Bui. 201, 100 p., 23 fig., 6 pi. 

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