Published in Nautilus, in 1974, in volume 88, pages 10-13

Published in Nautilus, in 1974, in volume 88, pages 31-32

Published in Nautilus, in 1974, in volume 88, pages 33-37

Published in Nautilus, in 1974, in volume 88, pages 69-79

Published in Nautilus, in 1974, in volume 88, pages 80-85

Published in Nautilus, in 1974, in volume 88, pages 86-89

Published in Nautilus, in 1974, in volume 88, pages 91-93

Published in Nautilus, in 1974, in volume 88, pages 94-100