Authors	Year	Title
Bisat	1928	The Carboniferous goniatite zones of England and their continental equivalents. Congrès de Stratigraphie Carbonifère, Heerlen 1927, C.R.B.: 117-133, pl.6, 6a; Liège.
Moore	1946	The Carboniferous goniatite genera Girtyoceras and Eumorphoceras. Proceedings of the Yorkshire Geological Society, 25: 387-445, 31 figs., pl.22-27; Wakefield.
Moore	1950	The Genus Sudeticeras and its Distribution in Lancashire and Yorkshire. Journal of the Manchester Geologists Association., 1950 (2): 31-50, pl.1-3; Manchester.