Cluster Headache

• University Department of Neurology CHR — Liège, Belgium
• Krankenhaus Lindenbrunn, Department of Neurology — Coppenbrügge, Germany
• Westdeutsches Kopfschmerzzentrum — Hufelandstr. 26, Hesse, Germany
• Migräne- und Kopfschmerzklinik Königstein — Königstein im Taunus, Königstein Im Taunus, Germany

• Citadelle Hospital — Liège, Belgium
• Danish Headache Center, Dept. of Neurology, Glostrup Hospital — Glostrup Municipality, Denmark
• Headache Center, Dept. of Neurology, University Duisburg-Essen — Essen, Germany
• Institut fur systemische Neurowissenschaften, Universitastsklinikum Hamburg-Eppendorf (UKE) — Hamburg, Germany

• APHM — Marseille, France

• Neurosciences department, Penrith Hospital, Cumbria Partnership NHS Foundation Trust — Penrith, Cumbria, United Kingdom

• Norwegian National Headache Centre St.Olavs Hospital — Trondheim, Norway

• CHU Lariboisière, AP-HP, Centre des Urgences Céphalées (Emergency Headacha Center) — Paris, Île-de-France Region, France

Not specified

• Jefferson Headache Center — Philadelphia, Pennsylvania, United States

• Valley Neurological Headache & Research Center — Phoenix, Arizona, United States
• Neurological Associates of Tucson — Tucson, Arizona, United States
• Northern California Headache Clinic — Mountain View, California, United States
• San Francisco Clinical Research Center — San Francisco, California, United States

• San Francisco Clinical Research Center — San Francisco, California, United States
• California Medical Clinic for Headache — Santa Monica, California, United States
• Colorado Neurology and Headache Clinic — Denver, Colorado, United States
• Diamond Headache Clinic — Chicago, Illinois, United States