(Holmqvist, Gustavsson, & Wernberg, in press)

Holmqvist, M., Gustavsson, L., & Wernberg, A., (in press). Variation theory - An organizing principle to guide design research in education. In A. E. Kelly, R. A. Lesh, & J. Y. Baek (Eds.), Handbook of design research methods in education. Mahwah, NJ: Lawrence Erlbaum Associates.