Ager, D. V. (1963). Principles of paleoecology: An introduction to the study of how and where animals and plants lived in the past. Mc Graw-Hill.
Lua i Stíl Chicago (17ú heag.)Ager, Derek Victor. Principles of Paleoecology: An Introduction to the Study of How and Where Animals and Plants Lived in the Past. New York: Mc Graw-Hill, 1963.
Lua MLA (9ú heag.)Ager, Derek Victor. Principles of Paleoecology: An Introduction to the Study of How and Where Animals and Plants Lived in the Past. Mc Graw-Hill, 1963.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.