Daniels, D. N., & Price, V. A. (2009). The essential enneagram: The definitive personality test and self-discovery guide (Revised and updated.). HarperOne.
Цитирование в стиле Чикаго (17-е изд.)Daniels, David N., и Virginia Ann Price. The Essential Enneagram: The Definitive Personality Test and Self-discovery Guide. Revised and updated. New York: HarperOne, 2009.
Цитирование MLA (8-е изд.)Daniels, David N., и Virginia Ann Price. The Essential Enneagram: The Definitive Personality Test and Self-discovery Guide. Revised and updated. HarperOne, 2009.
Предупреждение: эти цитированмия не могут быть всегда правильны на 100%.