Pigors, P. J. W., & Pigors, F. (1961). Case method in human relations: The incident process. McGraw-Hill.

Pigors, Paul John William, and Faith Pigors. Case Method in Human Relations: The Incident Process. New York: McGraw-Hill, 1961.

Pigors, Paul John William, and Faith Pigors. Case Method in Human Relations: The Incident Process. McGraw-Hill, 1961.