1. See for example: Craig, M., Thinking Visually, Continuum, London, 2002; ISBN 082644833-X; p52.
2. Guide to Quality Control;Ishikawa;Asian Productivity Organisation, Tokyo,1991
3. Koltze K., Souchkov V. Systematische Innovation, Hanser Verlag, 2011; ISBN 9783446421325; p125-136.
4. S. Ikovenko, Gen 3, MA TRIZ Level 3 training, April 2011.
5. Cameron G., TRIZICS, CreateSpace, 2010; ISBN 1456319892; p 49.