発明
↑ Forks, Phonographs, and Hot Air Balloons: A Field Guide to Inventive Thinking p. 8 (1992), by Robert J. Weber, also from Juice: The Creative Fuel That Drives World-Class Inventors, p. 13 (2004) by Evan I. Schwartz
↑ The Inventor's Notebook by Fred Grissom and David Pressman (2005); Leonardo da Vinci: Artist, Scientist, Inventor by Simona Cremante (2005), http://memory.loc.gov/ammem/collections/jefferson_papers/; http://www.alberteinstein.info/about/
↑ http://www.uspto.gov/web/offices/pac/mpep/documents/0200_201_08.htm
↑ White, Lynn: The Invention of the Parachute, Technology and Culture, Vol. 9, No. 3, (Jul., 1968), pp. 462-467
↑ See US Patent #5,461,114 and D11,023 as well as Leonardo da Vinci: Artist, Scientist, Inventor by Simona Cremante (2005)