Ager, D. V. (1963). Principles of paleoecology: An introduction to the study of how and where animals and plants lived in the past. McGraw-Hill.
Chicago-čujuhus (17. p.)Ager, Derek V. Principles of Paleoecology: An Introduction to the Study of How and Where Animals and Plants Lived in the Past. New York: McGraw-Hill, 1963.
MLA-čujuhus (9. p.)Ager, Derek V. Principles of Paleoecology: An Introduction to the Study of How and Where Animals and Plants Lived in the Past. McGraw-Hill, 1963.
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