Upper Paleozoic floral zones and floral provinces of the United States, with a glossary of stratigraphic terms by G.C. Keroher, in Shorter contributions to general geology

Read, C.B., and Mamay, S.H., 1964, Upper Paleozoic floral zones and floral provinces of the United States, with a glossary of stratigraphic terms by G.C. Keroher, in Shorter contributions to general geology: U.S. Geological Survey Professional Paper 454-K, p. K1-K35, 19 plates.