Columbia subject headings:
Louisiana Purchase--Boundaries--History.
Louisiana Purchase.
Mexico--Boundaries--United States.
Texas--History--Republic, 1836-1846.
United States--Boundaries--Mexico.
United States--Territorial expansion.
Harvard subject headings:
Louisiana Purchase
Mexico--Boundaries--United States.
Texas--History--Republic, 1836-1846
United States--Boundaries--Mexico.
Princeton subject headings: