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


  • Blieck, A., Elliott, D. and Gagnier, P. Y. (1991). Some questions concerning the phylogenetic relationships of heterostracans, Ordovician to Devonian jawless vertebrates. In M.-M. Chang et al. (Eds.), Early vertebrates and related problems of evolutionary biology. Science Press, Beijing.
  • Halstead, L. B. (1982). Evolutionary trends and the phylogeny of the Agnatha. In Problems of phylogenetic reconstruction, The Systematics Association Special Volume, No. 21, (ed. K. A. Joysey and A. E. Friday), pp. 159-196. Academic Press, London.
  • Janvier, P. (1996a). Early vertebrates. Oxford Monographs in Geology and Geophysics, 33, Oxford University Press, Oxford.
  • Janvier, P. (1996b). The dawn of the vertebrates: characters versus common ascent in current vertebrate phylogenies. Palaeontology, 39, 259-287.
  • Nelson, Joseph S. 1994. Fishes of the World, Third Edition. xvii + 600
  • Stensiö, E.A. (1964). Les Cyclostomes fossiles ou Ostracodermes. In: Traité de paléontologie (ed. J. Piveteau), Vol. 4(1), pp. 96-383, Masson, Paris


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