1. Abrahamsson, P., Salo, O., Ronkainen, J., and Warsta, J. (2002) Agile Software Development Methods: Review and Analysis, VTT Publications.
2. Abrahamsson, P., Warsta, J., Siponen, M. K., and Ronkainen, J. (2003) New directions on Agile method A comparative analysis. In: Proceedings of the 25th International Conference on Software Engineering, IEEE Computer Society, pp. 244–254.
3. Agile Alliance (2001) Principles behind the Agile Manifesto. Retrieved 14 May, 2009, from: http://agilemanifesto.org/principles.html .
4. Ambler S. W. (2002) Agile Modeling: Effective Practices for eXtreme Programming and the Unified Process. John Wiley & Sons.
5. Ambler S. W. (2004) The Object Primer, 3rd Edition. Cambridge University Press.