Enger, Eldon D. Environmental science : a study of interrelationships. - 6th ed. / - Boston, Mass. : WCB/McGraw Hill, c1998. - xxi, 456 p. : ill. (some col.), col. maps ; 29 cm. ISBN: 069728655X (case) 0697286568 (pbk.) Subjects--Topical Terms: Environmental sciences. Dewey Class. No.: 363.7 / SMI