Every effort has been taken to ensure that these materials comply with the requirements of copyright clearances and appropriate credits. Athabasca University will attempt to incorporate any corrections which are communicated to it.
The inclusion of any material in this publication is strictly in accord with the consents obtained and Athabasca University does not authorize or license any further reproduction or use without the consent of the copyright holder.
Dr. Joseph Wolpe's photograph is used with the kind permission of his wife, Eva Wolpe.