Arne Niemann is Professor of International Politics at the Department of Political Science, Johannes Gutenberg University Mainz, Germany.
Alexander Brand is Professor of Political Science/International Relations at Rhine-Waal University in Kleve, Germany.
Regina Weber is Researcher at the German Centre for Rail Traffic Research and Adjunct Lecturer at the Faculty of Society and Economics at Rhine-Waal University in Kleve, Germany.The three authors thank Florian Koch, Senior Lecturer at the Centre Interlangues (TIL), Université de Bourgogne (uB), for his contribution to the data collection.