Gordon, C. H. (1972). Before Columbus: Links between the old world and ancient America. Turnstone Press.
Chicago-viite (17. p.)Gordon, Cyrus H. Before Columbus: Links Between the Old World and Ancient America. London: Turnstone Press, 1972.
MLA-viite (8. p.)Gordon, Cyrus H. Before Columbus: Links Between the Old World and Ancient America. Turnstone Press, 1972.
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