United States Military Ranks

 Wikepedia 
 * United States Army Enlisted Rank Insignia
 * United States Army Officer Rank Insignia
 * United States Marine Corps Rank Insignia
 * United States Navy Officer Rank Insiginia
 * United States Navy Enlisted Rates
 * United States Air Force Officer Rank
 * United States Air Force Enlisted Rank

Internet Archives FamilySearch Digital library
 * United States Marine Corps. Ranks and Grades, 1775-1969
 * Joel William Bunkley,Military and naval recognition book; a handbook on the organization, insignia of rank, and customs of the service of the world's important armies and navies New York: D. Van Nostrand Company, 1917