The following bibliography has been generated by bringing together all references provided by our content partners. There may be duplication.

References

• Müller, U. & Ax, P. (1971). Gnathostomulida von der Nordseeinsel Sylt mit Beobachtungen zur Lebensweise und Entwicklung von Gnathostomula paradoxa Ax. Mikrofauna des Meeresbodens 9: 1-41. 
• Sterrer, W. (2013). WoRMS Gnathostomulida: World list of Gnathostomulida (version 2013-03-04). In: Species 2000 & ITIS Catalogue of Life, 11th March 2013 (Roskov Y., Kunze T., Paglinawan L., Orrell T., Nicolson D., Culham A., Bailly N., Kirk P., Bourgoin T., Baillargeon G., Hernandez F., De Wever A., eds). Digital resource at www.catalogueoflife.org/col/. Species 2000: Reading, UK.
• Sterrer, W. (1969). Beiträge zur Kenntnis der Gnathostomulida I. Anatomie und Morphologie des Genus Pterognathia Sterrer. Arkiv för Zoologi , Serie 2, 22(1): 1-125. 
• Sterrer, W. (2012). Haplognathia gubbarnorum (Sterrer, 1969). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=114743 on 2013-03-02
• Sterrer, Wolfgang / van der Steen, Louise J., ed. 1998. Gnathostomulida from the (sub)tropical northwestern Atlantic. Publications of the Foundation for Scientific Research in the Caribbean Region, vol. 142: Studies on the natural history of the Caribbean Region, vol. 74. 1-178
• Sterrer, Wolfgang. 1972. Systematics and evolution within the Gnathostomulida. Systematic Zoology, vol. 21, no. 2. 151-173
• Sterrer, Wolfgang. 2001. Gnathostomulida from Australia and Papua New Guinea. Cahiers de Biologie Marine, vol. 42, no. 4. 363-395
• UNESCO-IOC Register of Marine Organisms
• van der Land, J. (2001). Gnathostomulida, in: Costello, M.J. et al. (Ed.) (2001). European register of marine species: a check-list of the marine species in Europe and a bibliography of guides to their identification. Collection Patrimoines Naturels, 50: pp. 151