Environmental science : a study of interrelationships. Enger, Eldon D. Smith, Bradley F. Bockarie, Anne Todd. Environmental sciences 363 MCG 2006 A076 Or. Includes index. 2005 State Textbook Adoption - Rowan/Salisbury. Boston : McGraw-Hill, ℗♭2006. ℗♭2006. Text xxv, 476, 9, 2, 16 pages : http://catdir.loc.gov/catdir/toc/ecip0422/2004019843.html