	Authors	Year	Title
	Manger & Quinn	1972	Carboniferous dimorphoceratid ammonoids from northern Arkansas. Journal of Paleontology, 46: 303-314, fig.1-4, pl.1-2; Tulsa, Okla.
	Smith	1903	The Carboniferous Ammonoids of America. Monography, U.S. geological Survey, 42: 1-211, pl.1-29; Washington.