References

KG Harmon. (1999). Concussion in Sports. Retrieved February 21, 2011 from

      http://familydoctor.org/online/famdocen/home/common/brain/head/458.html

Kirsch TD, Lipinski CJ. Head injury. In: Tintinalli JE, Kelen GD, Stapczynski JS, Ma OJ, Cline DM, eds.Emergency Medicine: A Comprehensive Study Guide. 6th ed. Columbus, OH: McGraw-Hill; 2006:chap 255.

No Author. (2009). Heads Up: Concussion in Youth Sports. Retrieved February 28, 2011 from

            http://www.cdc.gov/concussion/pdf/parents

Ropper AH, Gorson KC. Clinical practice: concussion. N Engl J Med. 2007;356:166-172.

Visger G.  A Carrer of Concussions. (2010).  Retrieved on February 23, 2011 from
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