McFadden, Cynthia; Sherwood, Roxanna; Weinberg, Karin (April 29, 2007). "Science Behind 'The Secret'?". ABC News. Archived from the original on March 27, 2007. Retrieved November 23, 2020.
McFadden, Cynthia; Sherwood, Roxanna; Weinberg, Karin (April 29, 2007). "Science Behind 'The Secret'?". ABC News. Archived from the original on March 27, 2007. Retrieved November 23, 2020.
Collins, Tim (2010). Behind The lost symbol : the unauthorized guide to Dan Brown's bestselling novel. New York: Berkley Books. p. 87. ISBN978-1-101-19677-9. OCLC759839101.