Schneider RC. Serious and fatal neurosurgical football injuriesClin Neurosurg. 1964;12:226-236.
2.
Torg JS, Quedenfeld TC, Burstein A, Spealman AD, Nichols CE III. National Football Head and Neck Registry: report on cervical quadriplegia 1971-1975. Am J Sports Med.1979;7:127-132.
3.
Torg JS, Vegso JJ, O'Neill MJ, Sennett B. The epidemiologic, pathologic, biomechanical, and cinematographic analysis of football induced cervical spine trauma. Am J Sports Med. 1990;18:50-57.
4.
Wikipedia. The free encyclopedia. Available at: http://en.wikipedia.org/wiki/Theodore_Roosevelt%23_note-19. Accessed May 17, 2006.