(20 ILCS 1815/13) (from Ch. 129, par. 241)
    Sec. 13. Any commissioned officer or warrant officer, who shall have a combined total service of ten years (including service as an enlisted man), active and inactive in the Army of the United States, Navy, Marine Corps, or Coast Guard, or any reserves thereof, Officers' Reserve Corps, Organized Reserves, Enlisted Reserve Corps, Organized Militia, including the National Guard of the United States or the National Guard or Naval Militia of any State, or in one or more or in all of such services, may, upon his own request, be placed on the retired list and he shall be retired with the rank next higher than that held by him at the time of his retirement.
(Source: Laws 1951, p. 1999.)