1. Baskerville, R., Wood-Harper, A.T.: A Taxonomy of Action Research Methods. PAP012-0.05 (1996)
2. Benson, C., Müller-Prove, M.: Mzourek, Jiri: Professional Usability in Open Source Projects: GNOME, OpenOffice.org, NetBeans. In: CHI 2004. ACM, Vienna, Austria (2004)
3. Brooks, F.P.: The Mythical Man-Month: Essays on Software Engineering. Addison-Wesley, Reading (1995)
4. Habermas, J.: The Theory of Communicative Action. Beacon Press, London (1981)
5. Hippel, E.V.: Democratizing Innovation. MIT Press under the Creative Commons Rights (cc) (2005)