Published in Botanical Museum Leaflets, Harvard University, in 1956, in volume 17, pages 101-124

Published in Botanical Museum Leaflets, Harvard University, in 1956, in volume 17, pages 125-150

Published in Botanical Museum Leaflets, Harvard University, in 1956, in volume 17, pages 151-178

Published in Botanical Museum Leaflets, Harvard University, in 1956, in volume 17, pages 179-210

Published in Botanical Museum Leaflets, Harvard University, in 1956, in volume 17, pages 211-215

Published in Botanical Museum Leaflets, Harvard University, in 1956, in volume 17, pages 217-239