European educational concept in environmentalnature- and climate protection to safeguard a cross border sustainable developmentBarbara Tomaszewska, Aleksandra Kasztelewicz, Marta Dendys, Wiesław Bujakowski, Susanne Rahner, Michael Hartmann and Jürgen WeinreichE3S Web Conf., 66 (2018) 03005DOI: https://doi.org/10.1051/e3sconf/20186603005