	Authors	Year	Title
	Bisat	1924	The Carboniferous goniatites of the North of England and their zones. Proceedings of the Yorkshire Geological Society, 20: 40-124, pl.1-10; Leeds.
	Bisat	1934	The goniatites of the Beyrichoceras zone in the north of England. Proceedings of the Yorkshire Geological Society, 22: 280-309, fig.1-27, pl.17-24; Leeds.