APA (7th ed.) Citation

Center of Military History. (1999). Gettysburg staff ride: Briefing book. U.S. Army Center of Military History.

Chicago Style (17th ed.) Citation

Center of Military History. Gettysburg Staff Ride: Briefing Book. [Washington, D.C.?]: U.S. Army Center of Military History, 1999.

MLA (9th ed.) Citation

Center of Military History. Gettysburg Staff Ride: Briefing Book. U.S. Army Center of Military History, 1999.