http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
(based on the work of C.R. Clough and W. Gunn)
by R.G. Carruthers, G.A. Burnett and W. Anderson ; with petrological notes by H.H. Thomas.
At head of title: Explanation of sheets 3 & 5.
Memoirs of the Geological Survey of Great Britain