1. Day M. Sphenopalatine ganglion block. In: Manchikanti L, Singh V, editors. Interventional techniques in chronic non-spinal pain. Paducah: ASIPP Publishing; 2009. p. 101–14.
2. Sluder G. The role of the sphenopalatine ganglion in nasal headache. NY State J Med. 1908;27:8–13.
3. Ruskin S. Contributions to the study of the sphenopalatine ganglion. Laryngoscope. 1925;36:87–108.
4. Waldman S. Sphenopalatine ganglion block 80 years later. Reg Anesth Pain Med. 1993;18:274–6.
5. Eagle W. Sphenopalatine neuralgia. Arch Otolaryngol. 1942;35:66–84.