1. Ahlrichs, W.H. (1995) Ultrastruktur und Phylogenie von Seison nebaliae (Grube, 1859) und Seison annulatus (Claus, 1876). Hypothesen zu phylogenetischen Verwandtschaftsverhältnissen innerhalb der Bilateria. Göttingen: Cuvillier, 310 pp.
2. Ahlrichs, W.H. (1997) Epidermis ultrastructure of Seison nebaliae an Seison annulatus, and comparison of epidermal structures within the Gnathifera. Zoomorphology, 117, 41-48.
3. Alberts, B., Bray, D., Lewis, J., Raff, M., Roberts, K. & Watson, J.D. (1994) Molecular biology of the cell. New York: Garland Publishing, 1,310 pp.
4. Amin, O.M. (1985) Classification. In: Crompton, D.W.T. & Nickol, B.B. (Eds) Biology of the Acanthocephala. Cambridge: Cambridge University Press, pp. 27-72.
5. Amin, O.M. & Dailey, M.D. (1998) Description of Mediorhynchus papillosus (Acanthocephala: Giganthorhynchidae) from a Colorado, U.S.A., population, with a discussion of morphology and geographical variability. Journal of the Helminthological Society of Washington, 65, 189-200.