http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
139 pages : illustrations, maps (7 folded color in portfolio) ; 25 cm.
Prepared in cooperation with the Ohio Agricultural Experiment Station.
U. S. Soil Conservation Service. Soil survey, ser. 1949 ; no. 1