Under siege: man, men, and earth / Kenneth A. Wagner, Paul C. Bailey [and] Glenn Campbell. Wagner, Kenneth Allan, 1919- Bailey, Paul Clinton, joint author. Campbell, Glenn H., joint author. Ecology. Nature Effect of human beings on. Human beings Effect of environment on. QH541 .W23 1973 301.31 WAU Includes bibliographies. New York : Intext Educational Publishers, 1973. 1973. 1973 Text xii, 386 p. : eng