	Authors	Year	Title
	Clifton	1942	Invertebrate faunas from the Blaine and the Dog Creek Formations of the Permian Leonard Series. Journal of Paleontology, 16 (6): 685-699, pl.101-104; Tulsa,Oklahoma.
	Tharalson	1984	Revision of the Early Permian ammonoid family Perrinitidae. Journal of Paleontology, 58 (3): 804-833, fig.1-24, 1tab.; Lawrence, Kansas.