1. A. A. Powell, The Astral Body and other Astral Phenomena (Theosophical House, London, 1927).
2. S. Freud, Die Traumdeutung (Franz Deuticke, Leipzig und Wien, 1900).
3. Al’fred Adler, The Great Soviet Encyclopaedia, Ed. by A. M. Prokhorova (Sovetskaya Entsiklopediya, Moscow, 1969).
4. Yung Karl Gustav, The Great Soviet Encyclopaedia, Ed. by A. M. Prokhorova (Sovetskaya Entsiklopediya, Moscow, 1969).
5. V. S. Ramachandran, The Tell-Tale Brain. A Neuroscientist’s Quest for What Makes Us Human (W.W. Norton & Company, New York, London, 2011).