Gordon, C. H. (1972). Before Columbus: Links between the old world and ancient America. Turnstone Press.
Chicago-referens (17:e uppl.)Gordon, Cyrus H. Before Columbus: Links Between the Old World and Ancient America. London: Turnstone Press, 1972.
MLA-referens (8:e uppl.)Gordon, Cyrus H. Before Columbus: Links Between the Old World and Ancient America. Turnstone Press, 1972.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.