Wiegandt, Claus-C., Frank Osterhage, and Stefan Haunstein. “Polycentrism in Germany: A Comparative Study for Three City Regions”. Raumforschung und Raumordnung | Spatial Research and Planning 73, no. 3 (June 30, 2015): 167–183. Accessed May 15, 2025. https://rur.oekom.de/index.php/rur/article/view/578.