1. Calcareous Foraminifera in the Brownwood shale near Bridgeport, Texas Author/Creator: Plummer, Helen Jeanne Publication/Creation: Austin : The University of Texas, 1930 Resource Type: Book Access & Availability: Loading
2. Chart showing lithology, mineralogy, and paleontology of the Pennsylvanian Hermosa Group at Hermosa Mountain, La Plata County, Colorado Author/Creator: Geological Survey (U.S.) Publication/Creation: Denver, CO : For sale by U.S. Geological Survey Information Services Resource Type: Map Access & Availability: Loading