Paul Watzlawick, John H. Weakland, Richard Fisch (2011). “Change: Principles of Problem Formation and Problem Resolution”, p.11, W. W. Norton & Company
Paul Watzlawick, Janet Beavin Bavelas, Don D. Jackson, Bill O'Hanlon (2011). “Pragmatics of Human Communication: A Study of Interactional Patterns, Pathologies and Paradoxes”, p.255, W. W. Norton & Company
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