Introduction to appropriate technology : toward a simpler life-style / edited by R. J. Congdon ; ill. by Roy H. McCullagh. Congdon, R. J. Appropriate technology. Lifestyles. 338.91 COI Includes index. Bibliography: p. 200-202. Emmaus, Pa. : Rodale Press, c1977. c1977. 1977 Text xviii, 205 p. : eng