1. Alexander, C., Ishikawa, S., Silverstein, M., Jacobson, M., Fiksdahl-King, I., Angel, S.: A pattern language. Oxford University Press, New York (1977)
2. Alexander, C., Silverstein, M., Angel, S., Ishikawa, S., Abrams, D.: The Oregon Experiment. Oxford University Press, Oxford (1980)
3. Alexander, C.: The timeless way of building. Oxford University Press, Oxford (1979)
4. Beck, K.: EXtreme Programming Explained. Addison Wessley, London (1999)
5. Boehm, B., Hansen, W.J. (eds.): Spiral Development: Experience, Principles, and Refinements. In: Spiral Development Workshop, CMU/SEI-2000-SR-008 (2000), http://www.sei.cmu.edu/pub/documents/00.reports/pdf/00sr008.pdf