Ebel, K. 1992 04 15: Mode of life and soft body shape of heteromorph ammonites. Lethaia, Vol. 25, pp. 179–193. Oslo. ISSN 0024–1164.

Using the idea of a benthic mode of life for ammonites, based on a gastropod-like shell position, it is possible to reconstruct the development of all heteromorph ammonites by regarding single growth stages and the presumable acting forces. The reconstruction of shell formation, particularly the final shell position of heteromorphs with a hook, indicates that the soft body of the ammonite animal was considerably larger than comparison with the present-day Nautilus would suggest.