Published in Nautilus, in 2001, in volume 115, pages 1-14

Published in Nautilus, in 2001, in volume 115, pages 22-28

Published in Nautilus, in 2001, in volume 115, pages 36

Published in Nautilus, in 2001, in volume 115, pages 45-49

Published in Nautilus, in 2001, in volume 115, pages 50-54

Published in Nautilus, in 2001, in volume 115, pages 55-61

Published in Nautilus, in 2001, in volume 115, pages 84-89

Published in Nautilus, in 2001, in volume 115, pages 105-114

Published in Nautilus, in 2001, in volume 115, issue 3, pages 99-104

Published in Nautilus, in 2001, in volume 115, issue 4, pages 115-139

Published in Nautilus, in 2001, in volume 115, issue 4, pages 147-149