1. Aldridge, R.J., Briggs, D.E.G., Smith, M.P., Clarkson, E.N.K. and Clark, N.D.L. (1993) The anatomy of conodonts. Phil. Trans. R. Soc. 340B, 405?21.
2. Arsenault, M. and Janvier, P. (1991) The anaspid-like craniates of the Escuminac Formation (Upper Devonian) from Miguasha (Quebec, Canada), with remarks on anaspidpetromyzontid relationships. In Chang, M.-M., Liu, Y.-H. and Zhang, G.-R., eds. Early Vertebrates and Related Problems of Evolutionary Biology. Beijing: Science Press, pp. 19?40.
3. Ax, P. (1984) The Phylogenetic System. Chichester: Wiley, 340 pp.
4. Bardack, D. and Zangerl, R. (1968) First fossil lamprey: a record from the Pennsylvanian of Illinois. Science 162, 1265?7.
5. Belles-Isles, M. (1989) Mise en évidence de l'endosquelette postcrânien chez un Ostéostracé, Alaspis macrotuberculata Ørvig, du Dévonien supérieur de Miguasha (Québec). C. r. Acad. Sci. Paris 308, 1497?1501.