http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
Regional maps of vertical magnetic intensity in Illinois
12 pages : illustrations, maps (2 folded in pocket)
[by] Lyle D. McGinnis [and] Paul C. Heigold.
Circular (Illinois State Geological Survey) ; 324