	Authors	Year	Title
	Easton	1941	Pitkin limestone of northern Arkansas. Bulletin of the Geological Survey of Arkansas, 8: 1-115, pl.1-12;
	Easton	1943	The fauna of the Pitkin Formation of Arkansas. Journal of Paleontology, 17 (2): 125-154, fig.1, pl.21-24; Tulsa,Oklahoma.