1. Black, P. J., & Wiliam, D. (1998). Assessment and classroom learning. Assessment in Education, 5, 7–74.
2. Brousseau, G. (1997). Theory of didactical situations in mathematics, 1970–1990. Dordrecht: Kluwer.
3. Burkhardt, H. (1981). The Real World and Mathematics. Glasgow: Blackie (revised Nottingham: Shell Centre Publications 2000).
4. Burkhardt, H. (1988). The roles of theory in a “systems” approach to mathematical education, article in honor of prof. Hans-Georg Steiner’s 60th birthday. ZDM, 5, 174–177.
5. Burkhardt, H. (2006a). From design research to large-scale impact: Engineering research in education. In J. Van den Akker, K. Gravemeijer, S. McKenney & N. Nieveen (Eds.), Educational design research. London: Routledge.