1. Andrews, Frank M. and Withey, Stephen B. 1976. Social Indicators of Weil-Being. New York, N.Y. Plenum Press.
2. Arnold, Serena. 1980. "The Dilemma of Meaning,” Recreation and Leisure: Issues in an Era of Change, eds. Thomas L. Goodale and Peter A. Witt. State College, PA. Venture Publishing.
3. Berlyne, D.E. 1969. "Laughter, Humor and Play,” in The Handbook of Social Psychology Volume 3, eds. Gardner Lindzey and Elliot Aronson. Reading, MA. Addison Wesley.
4. Bishop, D.W. and Witt, P.A. 1970. "Sources of Behavioral Variance During Leisure Time." Journal of Personality and Social Psychology. 16. 352–60.
5. Brightbill, Charles K. 1963. The Challenge of Leisure. Englewood Cliffs, N.J. Prentice-Hall.