http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
Vertical-intensity magnetic map of Oklahoma
"Contouring based on data available through January 1964."
"Base map compiled by Geological Survey, U.S. Department of the Interior, 1950."
Includes "Index map of Oklahoma showing kind and quality of magnetic control," "Total-intensity aeromagnetic profiles over northeastern Oklahoma, " and "Key to named anomalies."