Published in Botanical Museum Leaflets, Harvard University, in 1952, in volume 15, pages 111-138

Published in Botanical Museum Leaflets, Harvard University, in 1952, in volume 15, pages 171-184

Published in Botanical Museum Leaflets, Harvard University, in 1952, in volume 15, pages 185-190

Published in Botanical Museum Leaflets, Harvard University, in 1952, in volume 15, pages 191-200

Published in Botanical Museum Leaflets, Harvard University, in 1952, in volume 15, pages 201-221

Published in Botanical Museum Leaflets, Harvard University, in 1952, in volume 15, pages 223-246

Published in Botanical Museum Leaflets, Harvard University, in 1952, in volume 15, pages 247-254

Published in Botanical Museum Leaflets, Harvard University, in 1952, in volume 15, pages 255-272