Townsend, Colin R. Essentials of ecology / Colin R. Townsend, Michael Begon, John L. Harper. - 2nd ed. - Malden, MA : Blackwell Pub., 2003. - xiii, 530 p. : ill., col. maps ; 24 cm. Includes bibliographical references (p. [501]-512) and index. ISBN: 1405103280 RM539.25 Subjects--Topical Terms: Ecology.