Rock units of the Precambrian basement in Colorado / by Ogden Tweto (Geology of the Precambrian basement in Colorado) (U.S. Geological Survey professional paper ; 1321-A)
Rock units of the Precambrian basement in Colorado / by Ogden Tweto
(Geology of the Precambrian basement in Colorado) (U.S. Geological Survey professional paper ; 1321-A)