1. The so-called hour-glass tumors of the spine;Heuer;Arch Surg,1929
2. Dumbbell (hourglass) neurofibromas affecting the spinal cord;Love;Surg Gynecol Obstet,1952
3. Dumbbell neurogenic tumors of the mediastinum;Akwari;Mayo Clin Proc,1978
4. Combined method for removing a neurogenic mediastinal intravertebral hourglass tumor;Irger;Zh Vopr Neirokhir (Moscow),1975
5. Combined approach to “dumbbell” intrathoracic and intraspinal neurogenic tumors;Grillo;Ann Thorac Surg,1983