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- United States — Territorial expansion
United States — Territorial expansion — Audiobooks
The Frontier in American History
by Frederick Jackson Turner
The Winning of the West, Volume 1
by Theodore Roosevelt
The Winning of the West, Volume 3
by Theodore Roosevelt
La Política de los Estados Unidos en el Continente Americano
by Raúl de Cárdenas y Echarte
The Winning of the West, Volume 2
by Theodore Roosevelt
The Winning of the West, Volume 4
by Theodore Roosevelt
The Path of Empire: A Chronicle of the United States as a World Power
by Carl Russell Fish