Barzel, B. & Biehler, R. Theory-based design of professional development for upper secondary teachers – focusing on the content specific use of digital tools. In S. Zehetmeier, D. Potari & M. Ribeiro (Hrsg.), Professional Development and Knowledge of Mathematics Teachers. Oxon: Routledge.
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Barzel, B. & Biehler, R. Theory-based design of professional development for upper secondary teachers – focusing on the content specific use of digital tools. In S. Zehetmeier, D. Potari & M. Ribeiro (Hrsg.), Professional Development and Knowledge of Mathematics Teachers. Oxon: Routledge.