Behavior modification. Bandura, Albert. Principles of behavior modification. New York: Holt, Rinehart & Winston, 1969, 677 p., $ 9.95. Eysenck, H. J. (ed.) Experiments in behaviour therapy. New York: Pergamon Press, 1967, 558 p., $17.00. Yates, Aubrey J. Behavior therapy. New York: John Wiley & Sons, 1970, 445 p., $13.95