	Authors	Year	Title
	Becker & House	1993	New early Upper Devonian (Frasnian) goniatite genera and the evolution of the "Gephurocerataceae". Berliner geowissenschaftliche Abhandlungen (E), 9: 111-133, fig.1-4, pl.1-2; Berlin.
	Becker, House & Menner	2000	Revision of ammonoid biostratigraphy in the Frasnian (Upper Devonian) of the Southern Timan (Northeast Russian Platform). [R.T.Becker,M.R.House,V.V.Menner & N.S.Ovnatanova]. Acta Geologica Polonica, 50: 67-97, 10 text-figs., 3 tabls., 4 pls., Warszawa.
	Bogoslovsky	1971	Devonskie ammonoidei. II. Goniatity. Trudy paleont. Inst.Akad. Nauk SSSR, 127: 1-228, fig.1-67, pl.1-19; Moskva.