Published in Nautilus, in 1959, in volume 72, pages 111-113

Published in Nautilus, in 1959, in volume 72, pages 115

Published in Nautilus, in 1959, in volume 73, pages 1-9

Published in Nautilus, in 1959, in volume 73, pages 9-11

Published in Nautilus, in 1959, in volume 73, issue 1, pages 36