	Authors	Year	Title
	Miller & Furnish	1958a	Middle Pennsylvanian Schistoceratidae (Ammonoidea). Journal of Paleontology, 32 (2): 253-268, fig.1-9, pl.33-34; Tulsa,Oklahoma.
	Schmidt	1955	Einige Goniatiten aus spanischem Oberkarbon. Publications Ass. Étud. Paléont., 21: 49-59, pl.A; Bruxelles.