Reconnaissance erosion survey of the State of California
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"California erosion survey of 1934 by E.J. Carpenter in charge ... Acknowledgement is made to College of Agriculture, University of California, for assistance.|~|U.S. Dept. of Agriculture, Soil Conservation Service ; field survey under direction of G.L. Fuller ; map compiled by W.F. Beamon, chief draftsman.|~|"Base map by U.S. Geological Survey, 1929."
United States. Soil Conservation Service.