Nikola Tesla (2002). “Nikola Tesla on His Work with Alternating Currents and Their Application to Wireless Telegraphy, Telephony, and Transmission of Power: An Extended Interview”, p.110, 21st Century Books
Edward Sapir, David Goodman Mandelbaum (1985). “Selected Writings of Edward Sapir in Language, Culture and Personality”, p.395, Univ of California Press
Edward Sapir, David Goodman Mandelbaum (1985). “Selected Writings of Edward Sapir in Language, Culture and Personality”, p.394, Univ of California Press
Scott Bedbury, Stephen Fenichell (2003). “A New Brand World: Eight Principles for Achieving Brand Leadership in the Twenty-First Century”, p.39, Penguin