Janvier P., Lund R. (1983). Hardistiella montanensis n. gen. et sp. (Petromyzontida) from the Lower Carboniferous of Montana, with remarks on the affinities of lampreys. J. Vert. Palent, 2, 407-413.
Moy-Thomas J. A., Miles R.S. (1971). Palaeozoic Fishes (2d ed.). Chapman and Hall, Ltd, London.
Northcutt R. G., Gans C. (1983). The genesis of neural crest and epidermal placodes: A reinterpretation of vertebrate origins. Quart. Rev. Biol, 58, 1-28.
Novitskaya L. I. (1971). Les amphiaspides (Heterostraci) du Devonien de la Siberie. Cahiers de Paleontologie, Paris 1971, 1-130.
Pan Jiang (1984). The phylogenetic position of the Eugaleaspi- da in China. Proc. Linn. Soc. N.S.W, 107 (3), 309-319.
Repetski J. E. (1978). A fish from the Upper Cambrian of North America, Science, 200, 529-531.
Ritchie A. (1968a). New evidence of Jaymoitius kerwoodi White, an important ostracoderm from the Silurian of Lanarkshire, Scotland. Paleontology, 11, 21-39.
Ritchie A. (1968b). Phlebolepis elegans Pander, an Upper Silurian thelodont from Oesel, with remarks on the morphology of thelodonts. In: T. Ritchie A., Gilbert-Tomlinson J. (1977). First Ordovician vertebrates from the Southern Hemisphere. Alcheringa, 1, 351-368.
Ruben J. A., Bennett A. F. (1980). Antiquity of the vertebrate pattern of activity metabolism and its possible relation to vertebrate origin. Nature, 286, 886-888.
Schaeffer В., Thomson К. S. (1980). Reflections on agnathan- gnathostome relationships. In: L. L. Jacobs (ed.), Aspects of Vertebrate History, pp. 19-33. Museum of Northern Arizona Press, Flagstaff.
Stensid E. (1963). The brain and the cranial nerves in fossil, lower craniate vertebrates. Skrifter utgitt av Det Norske Videns kaps-Akademi i Oslo. I. Mat.-Naturv. Kl. Ny Ser, 13, 1-120.
Stensio E. (1964). Les Cyclostomes fossiles ou Ostracodermes. In: J. Piveteau (ed.), Traite de Paleontologie, Tome IV, vol.