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- United States — History -- Civil War, 1861-1865 -- Secret service
United States — History -- Civil War, 1861-1865 -- Secret service — Audiobooks
Nurse and Spy in the Union Army
by S. Emma E. (Sarah Emma Evelyn) Edmonds
The Spy of the Rebellion
by Allan Pinkerton
The Boy Spy
by Joseph Orton Kerbey