http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
study of the surface areas of particulate microcrystalline silica and silica sand
Department of Registration and Education.
R.N. Leamnson, Josephus Thomas, Jr., H.P. Ehrlinger III.
At head of title: State of Illinois Department of Registration and Education.
Circular (Illinois State Geological Survey) ; 444