Published in Nautilus, in 1966, in volume 79, pages 101-103

Published in Nautilus, in 1966, in volume 80, pages 24-28

Published in Nautilus, in 1966, in volume 80, pages 46-52

Published in Nautilus, in 1966, in volume 80, pages 52-53

Published in Nautilus, in 1966, in volume 80, pages 53-56