*Bernd Zimmermann, Torsten Fritzlar, Lenni Haapasalo - et al. -- Possible gain of IT in problem-oriented learning environments from the viewpoint of history of mathematics and modern learning theories | *Bernd Zimmermann, Torsten Fritzlar, Lenni Haapasalo - et al. -- Possible gain of IT in problem-oriented learning environments from the viewpoint of history of mathematics and modern learning theories |