Published in Botanical Museum Leaflets, Harvard University, in 1960, in volume 19, pages 33-56

Published in Botanical Museum Leaflets, Harvard University, in 1960, in volume 19, pages 97-108

Published in Botanical Museum Leaflets, Harvard University, in 1960, in volume 19, pages 109-122

Published in Botanical Museum Leaflets, Harvard University, in 1960, in volume 19, pages 123-124