Army Study Guide. "NCO Ranks and Positions Explained." (April 26, 2011)http://www.armystudyguide.com/content/army_board_study_guide_topics/nco_duties/nco-ranks-and-positions
The Institute of Heraldry. "NCO Professional Development Ribbon."Office of the Administrative Assistant to the Secretary of the Army. (April 21, 2011)http://www.tioh.hqda.pentagon.mil/Awards/nco_professional.aspx
Nelson, Sgt. 1st Class Margaret C. Headquarters, Department of the Army, Office of the Chief of Public Affairs (Media Relations), Personnel and Human Resources Team. Personal interview by telephone. April 25, 2011.
PBS. "Sergeant Patrick Gass." Lewis and Clark. Inside the Corps. (Accessed April 29, 2011)http://www.pbs.org/lewisandclark/inside/pgass.html
Rush, CSM Robert S, U.S. Army, Retired. NCO Guide: Ninth Edition. Stackpole Books, Mechanicsburg, Pa. 2010.
Tice, Jim. "Tough new enlisted courses on the way." Army Times. Sept. 14, 2009. (Accessed April 22, 2011)http://www.armytimes.com/news/2009/09/army_NCOES_091409w/
U.S. Army. "NCO Education System Information." (Accessed April 27, 2011)http://www.armyncoes.com/
U.S. Army. "Sergeants Major Academy." (Accessed April 29, 2011)https://usasma.bliss.army.mil/site/page.asp?c=about/about.html&r=about/about-r.html&t=About
U.S. Army Training and Doctrine Command (TRADOC). Interview by e-mail. April 27, 2011.
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