1. Albright, R.G., Cranial kinetics of the generalized colubrid snake Elaphe obsolete quadrivitata, J. Morphol., 1959, vol. 105, no. 2, pp. 193–225.
2. Bäckström, K., Rekonstruktionsbilder zur Ontogenie des Koopfskelettes von Tropidonotus natri, Acta Zool. (Stock.), 1931, vol. 12, pp. 83–144.
3. de Beer, G.R., Contributions to the development of the skull in sturgeons, Quart. Journ. Micr. Sci., 1925, vol. 69, pp. 671–687.
4. de Beer, G.R., Studies on the vertebrate head. II. The orbito-temporal region of the skull, Quart. Journ. Micr. Sci., 1926, vol. 70, pp. 263–370.
5. de Beer, G.R., The development of the skull of Scyllium (Scyliorhinus) canicula L., Quart. Journ. Micr. Sci., 1931, vol. 74, pp. 591–646.