Freiburg, Baden-Württemberg, Germany
Cali, Valle del Cauca, Colombia
Kazan, Tatarstan, Russian Federation
Freiburg im Breisgau, Baden-Württemberg, Germany
Philadelphia, PA, USA
Singapore, Singapore
Madrid, Community of Madrid, Spain
Saarbrücken, Saarland, Germany
Seattle, WA, USA
Ciudad de la Costa, Departamento de Canelones, Uruguay
Sofia, Bulgaria