Principles of paleoecology : an introduction to the study of how and where animals and plants lived in the past / Ager, D. V. (Derek Victor) Paleoecology. QH542 .A4 560 AGP Includes bibliographical references and index. New York : McGraw-Hill, c1963. c1963. 1963 Text xi, 371 p. : eng International series in the earth sciences