1. Scaling up innovations through learning alliances: An introduction to the approach;Smits,2007
2. Experiences in appropriate technology;Mitchell,1980
3. Small is beautiful: economics as if people mattered;Schumacher,1973
4. Appropriate technology – tools, choices, and implications;Hazeltine,1999
5. Introduction to appropriate technology – toward a simpler life-style;Congdon,1977