http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
Type sections and stratigraphy of the members of the Blackleaf and Marias River Formations (Cretaceous) of the Sweetgrass arch, Montana
a report of a formal subdivision and age assignments of a classic Cretaceous area
Geological Survey professional paper ; 974