Authors
Petr Schlegel
Faculty of Education, University of Hradec Králové, Hradec Králové
Adam Křehký
Faculty of Education, University of Hradec Králové, Hradec Králové
© 2019 Petr Schlegel, Adam Křehký, published by Sciendo
This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License.