Authors Year Title
Furnish & Spinosa 1966 Historic Pennsylvanian Ammonoids from Iowa.
Iowa Academy of Science, 73: 253-259, fig.1-2.
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.
Wiedey 1929 A new species of an exotic group of Carboniferous goniatites.
American Journal of Science, 5th Series, Volume 17: 321-325 fig.1-7; New Haven, Conn.