Pigors, P. J. W., & Pigors, F. (1961). Case method in human relations: The incident process. McGraw-Hill.
توثيق أسلوب شيكاغو (الطبعة السابعة عشر)Pigors, Paul John William, و Faith Pigors. Case Method in Human Relations: The Incident Process. New York: McGraw-Hill, 1961.
توثيق جمعية اللغة المعاصرة MLA (الإصدار التاسع)Pigors, Paul John William, و Faith Pigors. Case Method in Human Relations: The Incident Process. McGraw-Hill, 1961.