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.
Foord & Crick 1897 Catalogue of the fossil Cephalopoda in the British Museum (Natural History). Part III, containing the Bactritidae and part  of the Suborder Ammonoidea).
pp.I-XXXIII, 1-303, 145 figs., London.