1. Cluster headaches. Mechanisms and management;Kudrow,1980
2. Histaminic cephalgia;Horton;JAMA,1956
3. A clinical comparison of cluster headache and migraine;Ekbom;Acta Neurol Scand,1970
4. Cancer ward;Solzhenitsyn,1969
5. Cluster headache developing following ipsilateral orbital exenteration;McKinney;Headache,1983