	Authors	Year	Title
	Korn	1999	Famennian Ammonoid Stratigraphy of the Ma'der and Tafilalt (Eastern Anti-Atlas, Morocco. Abhandlungen der Geologischen Bundesanstalt, 54: 147-179, 9 figs., 1 tabl., 7 pls., Wien.
	Price	1982	Some Famennian (Upper Devonian) ammonoids from north western Europe. [unpublished dissertation, Hull]. Unpubl.Ph.D. Thesis,I-XXV,1-460,fig.1.1-1.7,fig.3.1-3.3,fig.4.1-4.16, fig.5.1-5.35, fig.6.1, fig.7.1-7.21, fig.8.1-8.2, pl.5.1-5.42, pl.7.1-7.6; Hull.
	Schmidt	1924	Zwei Cephalopodenfaunen an der Devon-Carbongrenze im Sauerland. Jahrbuch der Preußischen Geologischen Landesanstalt, 44 (for 1923): 98-171, fig.1-5, pl.6-8; Berlin.