Plant ecology / John E. Weaver and Frederic E. Clements. Weaver, John E. 1884-1966. Clements, Frederic E. 1874-1945, Plant ecology. QK901 .W4 1938 581.5 WEP Includes index. Bibliography: p. 539-582. New York : McGraw-Hill Book , c1966 c1966 1938 Text xxii, 601 p. : eng McGraw-Hill publications in the botanical sciences