Šablon:Scientific American Frontiers
„Scientific American Frontiers, on season 1” (en). Scientific American Frontiers. PBS. 1990–1991. Arhivirano iz originala na datum 2006.
„Scientific American Frontiers, on season 1” (en). Scientific American Frontiers [en]. PBS. 1990–1991. Arhivirano iz originala na datum 2006.
