Authors Year Title
Frech 1897- Lethaea geognostica oder Beschreibung und Abbildung der für die Gebirgs-Formationen bezeichnendsten Versteinerungen. I. Theil. Lethaea palaeozoica. 2. Band.
35pls, 6maps, 551figs.; Stuttgart.
Plummer & Scott 1937 Upper Paleozoic ammonites in Texas.
The geology of Texas, vol.3 pt.1, Bull. Texas. Univ., 3701: 1-516, fig.1-88, pl.1-41; Austin, Texas.
Smith 1903 The Carboniferous Ammonoids of America.
Monography, U.S. geological Survey, 42: 1-211, pl.1-29; Washington.
White 1891 The Texas Permian and its Mesozoic types of fossils.
Bulletin of the United States Geological Survey, No.77: 1-51, pl.1-4; Washington.