1. Abel, Othenio. 1912. Grundzüge der Paläobiologie der Wirbelthiere. Stuttgart: E. Schweizerbart.
2. Ager, Derek V. 1963. Principles of Paleoecology: An Introduction to the Study of How and Where Animals and Plants Lived in the Past. New York: McGraw-Hill.
3. Ager, Derek V. 1965. “The Adaptations of Mesozoic Brachiopods to Different Environments.” Palaeogeography, Palaeoclimatology, Palaeoecology 1: 143–172.
4. Beerbower, James R. 1960. Search for the Past: An Introduction to Paleontology. Englewood Cliffs: Prentice-Hall.
5. Briggs, Derek E. G. (ed.). 2005. Evolving Form and Function: Fossils and Development. New Haven: Peabody Museum.