http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
prepared by the Arizona Bureau of Mines, University of Arizona ; by Eldred D. Wilson and Richard T. Moore with additional data from maps by F.L. Ransome [and others].
"Contour interval 500 feet. Datum is mean level."
Insets: Index map of Arizona showing location of Mohave County, Arizona. Map showing sources of topographic data. Map showing sources of geologic data.