Published in Nautilus, in 1960, in volume 73, pages 103-109

Published in Nautilus, in 1960, in volume 73, pages 110-113

Published in Nautilus, in 1960, in volume 73, pages 113

Published in Nautilus, in 1960, in volume 73, pages 125-129

Published in The Nautilus, in 1960, in volume 73, issue 4, pages 158-159

Published in Nautilus, in 1960, in volume 74, pages 15-18

Published in Nautilus, in 1960, in volume 74, pages 56-62

Published in Nautilus, in 1960, in volume 74, pages 75-78