1. Danish Headache Center, Department of Neurology, Rigshospitalet– Glostrup, Faculty of Health and Medical Sciences, University of Copenhagen, Glostrup, Denmark.
2. School of Behavioral and Brain Sciences, Center for Advanced Pain Studies, The University of Texas at Dallas, Richardson, USA.
3. Danish Headache Knowledge Center on Headache Disorders, Rigshospitalet – Glostrup, Glostrup, Denmark.