1. Rozen T: Trigeminal autonomic cephalalgias. Continuum Headache 2006, 6:171–193.
2. Headache Classification Committee of the International Headache Society: The International Classification of Headache Disorders 2nd ed. Cephalalgia 2004 24(Suppl 1):1–160.
3. May A: Cluster headache: pathogenesis, diagnosis, and management. Lancet 2005, 366:843–855.
4. Dodick DW, Rozen TD, Goadsby PJ, et al.: Cluster headache. Cephalalgia 2000, 20:787–803.
5. Leone M, D’Amico D, Attanasio A, et al.: Verapamil is an effective prophylactic for cluster headache: results of a double blind multicenter study versus placebo. In: Cluster Headache and Related Conditions. Edited by Olesen J, Goadsby PJ. Oxford: Oxford University Press; 1999:296–299.