	Authors	Year	Title
	Fredericks	1921	O nekotorykh verkhnekamennougol'nykh ammoneyakh Urala. Ezhegodnik Russkogo Paleontologicheskogo Obshchestva, 3: 73-94, fig.1, pl.5; Petrograd.
	Gerasimov	1937	Ural'skii otdel permskoi sistemy. Uchenye zapiski Kazanskogo gosudarstvennogo universiteta, 97, kniga 3-4, geologiia, vyp.8-9): 3-68, pl.1-2; Kazan.