http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
Basement map of North America between latitudes 24 ̊and 60 ̊N
American Association of Petroleum Geologists
by the American Association of Petroleum Geologists and the United States Geological Survey; prepared by the Basement Rock Project Committee, Peter T. Flawn, chairman, 1957-66. Douglas M. Kinney, editor, U. S. Geological Survey.
Inset: Map showing areas of responsibility of committee members and associated contributors.
Shows contours on basement surface, faults, and age of basement rocks.
Scale 1:5,000,000. approx. 1 in. to 80 miles