1911 Encyclopædia Britannica/Arikara

ARIKARA, or Aricara (from ariki, horn), a tribe of North American Indians of Caddoan stock. They are now settled with the Hidatsas and the Mandans on the Fort Berthold Reservation, North Dakota. They originally lived in the Platte Valley, Nebraska, with the Pawnees, to whom they are related. They number about 400.

See Handbook of American Indians, ed. F. W. Hodge (Washington 1907)