Ketamine‐Magnesium for Refractory Chronic Cluster Headache: A Case Series. - Moisset, Xavier; Giraud, Pierric; Meunier, Estelle; Condé, Sakahlé; Périé, Maud; Picard, Pascale; Pereira, Bruno; Ciampi de Andrade, Daniel; Clavelou, Pierre; Dallel, Radhouane (Headache: The Journal of Head & Face Pain, 2020)