1. The development of the skull and visceral arches in Lepidosiren and Protopterus;Agar;Trans. Roy. Soc. Edin.,1906
2. The cranial muscles and cranial and first spinal nerves in Amia calva;Allis;J. Morph.,1897
3. Assheton , R. 1907 Development of skull in Gymnarchus. Budgett Memorial Volume 293
4. Berg , L. S. 1947 Classification of Fishes, both recent and fossil . English translation:
5. The development of the chondrocranium in Acipenser;Edwards;Quart. J. micr. Sci.,1925