1. Department of Neurology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, South Korea
2. Danish Headache Center, Department of Neurology, Rigshospitalet Glostrup, Faculty of Health and Medical Sciences, University of Copenhagen, Denmark
3. Department of Neurology, Charité Universitätsmedizin Berlin, Greifswald, Germany
4. Board of Directors, Universitätsmedizin Greifswald, Greifswald, Germany