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8
Report of the National Conservation Commission, with accomp..
United States congressional serial set ; serial set no. 5399;Senate document / 60th Congress, 2nd session. Senate ; no. 676, vol.3
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9
Papers on the conservation of mineral resources, reprinted ..
United States congressional serial set ; serial set no. 5466;House document / 60th Congress, 2nd session. House ; no. 1554