1. Calloway Creek limestone and Ashlock and Drakes formations (Upper Ordovician) in south-central Kentucky Author/Creator: Weir, Gordon W. 1922-2011, (Gordon Whitney), author Publication/Creation: [Washington, D.C.] : United States Department of the Interior, Geological Survey, 1965 Resource Type: Book Access & Availability: Loading
2. Cambrian and Ordovician rocks of southern Arizona and New Mexico and westernmost Texas Author/Creator: Hayes, Philip T. 1923- (Philip Thayer), author Publication/Creation: Washington : United States Department of the Interior, Geological Survey, 1975 Resource Type: Book Access & Availability: Loading
3. Carbonate rocks of Cambrian and Ordovician age in the Lancaster quadrangle, Pennsylvania Author/Creator: Meisler, Harold, author Publication/Creation: [Washington, D.C.] : United States Department of the Interior, Geological Survey, 1968 Resource Type: Book Access & Availability: Loading
4. The Chopawamsic Formation-- : a new stratigraphic unit in the Piedmont of northeastern Virginia Author/Creator: Southwick, D. L. 1936- (David Leroy), author Publication/Creation: [Washington, D.C.] : United States Department of the Interior, Geological Survey, 1971 Resource Type: Book Access & Availability: Loading
5. Clays Ferry formation (Ordovician) -- a new map unit in south-central Kentucky Author/Creator: Weir, Gordon W. 1922-2011, (Gordon Whitney), author Publication/Creation: [Washington, D.C.] : United States Department of the Interior, Geological Survey, 1965 Resource Type: Book Access & Availability: Loading
6. Composition, clay mineralogy, and diagenesis of the Simpson Group (Middle Ordovician), Grady County, Oklahoma Author/Creator: Pollastro, Richard M., author Publication/Creation: [Reston, Va.] : U.S. Department of the Interior, U.S. Geological Survey, 1991 Resource Type: Book Access & Availability: Loading
7. Composition, clay mineralogy, and diagenesis of the Simpson Group (Middle Ordovician), Grady County, Oklahoma Author/Creator: Pollastro, Richard M. Publication/Creation: [Washington, D. C.] : U.S. G.P.O. ; Denver, CO : For sale by the Books and Open-File Reports section, 1991 Resource Type: Book Access & Availability: Loading
8. Contributions to the Ordovician paleontology of Kentucky and nearby states Publication/Creation: Washington : United States Department of the Interior, Geological Survey, 1979 Resource Type: Book Access & Availability: Loading
9. Cross sections of Lower Ordovician carbonate depositional lithofacies and Mississippi Valley-type zinc-and iron-sulfide mineralization in the Caulfield district, east-central part of Harrison 1⁰ x 2⁰ quadrangle, Arkansas and Missouri Author/Creator: Geological Survey (U.S.) Publication/Creation: Denver, CO : For sale by Map Distribution Resource Type: Map Access & Availability: Loading