United States Army in World War II . The Technical Services. The Signal Corps: the Test (December 1941 to July 1943). George Raynor Thompson, Dixie R. Harris, Pauline M. Oakes, and Dulany Terrett. Office of the Chief of Military History, Department of the Army, Washington, D.C., 1957 (order from Supt. of Documents, GPO, Washington 25). xv + xx +621 pp. Illus. $4.50.