References
- Hughes, Thomas P. (1977). "Edison's method". In Pickett, W. B. Technology at the Turning Point. San Francisco: San Francisco Press. pp. 5–22.
- Hughes, Thomas P. (2004). American Genesis: A Century of Invention and Technological Enthusiasm (2nd ed.). Chicago: University of Chicago Press. ISBN 978-0-22635-927-4.
- J.K.Rowling. (2004). Harry Potter and the Prisoner of Azkaban, 2004, Spoken by character Albus Dumbledore
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