1. Organic geochemistry of black shales, marlstones, and oils of middle Pennsylvanian rocks from the northern Denver and southeastern Powder River Basins, Nebraska and Wyoming Publication/Creation: Denver, CO : For sale by Book and Open-File Report Sales, U.S. Geological Survey Resource Type: Book Access & Availability: Loading
2. On some new genera and species of Pennsylvanian fossils from the Wewoka formation of Oklahoma Author/Creator: Girty, George Herbert, 1869-1939 Publication/Creation: New York : New York Academy of Sciences, 1911 Resource Type: Book Is Part Of: Annals of the New York Academy of Sciences, v. 21. Access & Availability: Loading