1. Department of Geography, University of Utah, Salt Lake City, UT, USA
2. Geographical Science, Department of Social and Economic Geography, Geography Faculty, Lomonosov Moscow State University, Moscow, Russia
3. Geographical Science, Department of Social and Economic Geography, Faculty of Geography, Lomonosov Moscow State University, Moscow, Russia
4. Geographical Science, Department of Socio-Economic Geography, Institute of Geography, Russian Academy of Sciences, Moscow City Division of the Russian Geographical Society, Moscow, Russia