	Authors	Year	Title
	Bogoslovskaya	1990	Osnovye puti razvitiya i klassifikatsiya pozdnepaleozoyskikh ammonoidey Marathonitaceae i Cyclolobaceae. Trudy Paleontologicheskogo Instituta Akademiya Nauk SSSR, 243: 70-86, fig.1-3; Moskva.
	King, Dunbar & Cloud	1944	Geology and Paleontology of the Permian area northwest of Las Delicias, southwestern Coahuila, Mexico. [King,R.E., Dunbar,C.O., Cloud,P. & Miller,A.K.] Geological Society of America Special Papers, 52: X + 1-172, 29 text-figs., 45 pls.