1Department of Neurology, Thomas Jefferson University, Philadelphia, PA USA
2Department of Neurology, University Hospital Halle (Saale) and University Halle-Wittenberg, Halle, Germany
3Teva Pharmaceutical Industries, West Chester, PA USA
4Department of Neurology and Westgerman Headache Center Essen, University Hospital, Essen, Germany
5California Medical Clinic for Headache, Santa Monica, CA USA
6Headache Medical Centre, Linz, Austria
7Department of Neurology, Konventhospital Barmherzige Brüder, Linz, Austria
© The Author(s) 2022
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