Spangenberg, George A. George A. Spangenberg Oral History互联网档案馆的存檔,存档日期2008-09-10.. www.spangenberg.org. Judith Spangenberg-Currier, ed. pp.187-190. Accessed on 29 April 2008.
Aastad, Andy. "The Introduction to the JetRanger".互联网档案馆的存檔,存档日期September 10, 2008,. Rotor Magazine. Helicopter Association International. Winter 2006-2007. Accessed on 5 April 2009.
Spangenberg, George A. George A. Spangenberg Oral History互联网档案馆的存檔,存档日期2008-09-10.. www.spangenberg.org. Judith Spangenberg-Currier, ed. pp.187-190. Accessed on 29 April 2008.
Aastad, Andy. "The Introduction to the JetRanger".互联网档案馆的存檔,存档日期September 10, 2008,. Rotor Magazine. Helicopter Association International. Winter 2006-2007. Accessed on 5 April 2009.